Borg Mechanical Digital BL5051 - Back-to-Back Lever/Lever - Multiple Finishes - Including Marine Grade Pro
At A Glance
DISPATCHSame Day Before 11am
PIN Code (Outside) PIN Code (Inside) 
Mechanical Key(Not on This Model)
The Borg BL5051 is a medium-heavy duty fully mechanical digital lock in a back-to-back (BTB) lever/lever configuration - a complete keypad and lever on both faces of the door, so a code is required to pass through in either direction. Each keypad has its own independent coding chamber, allowing a different code on each side. It is the tumbler code change version of the BL5051 family: codes are set on the bench with the supplied tweezers, which suits sites where the code rarely changes - see why double-sided locks suit gates.
This listing covers three finish variants selected on this page: Polished Chrome (BL5051MG), Satin Chrome (BL5051SC) and Black (BL5051MGPRO). The Black variant is not simply a colour choice - BL5051MGPRO carries Marine Grade Pro construction: 316 stainless steel internal components under Borg's MG Pro marine coating, tested to 1,000 hours of continuous salt spray. The chrome variants use external grade and PVD finishes and are not rated for coastal positions.
The BL5051 is fire rated to AS 1905.1-2005 (up to 4 hours depending on the doorset), cycle tested past 100,000 operations, reversible on site, and fits doors 35mm to 80mm thick on the standard fixings. Because it is entirely mechanical there are no batteries, no wiring and nothing electronic to fail - browse the full battery-free range in our Digital Mechanical Locks category.
Estimated Dispatch
Usually ships same day if ordered before 11am AEST (excludes weekends and Queensland public holidays).
Usually ships same day if ordered before 11am AEST (excludes weekends and Queensland public holidays).
BL5051MGPRO (Black) - Marine Grade Pro, Not Just a Colour
The Black variant is built with 316 stainless steel internal components and MG Pro black marine external coating, tested to 1,000 hours of continuous salt spray with corrosion resistance warranted for 12 months. This is a fundamentally different specification to the Polished Chrome (BL5051MG, external grade) and Satin Chrome (BL5051SC, PVD) variants. Choose Black MG Pro for coastal, beachside, poolside and marine positions; choose Polished Chrome or Satin Chrome for sheltered or interior doors. Background: do you actually need MG Pro? and the honest brand corrosion comparison.
The Black variant is built with 316 stainless steel internal components and MG Pro black marine external coating, tested to 1,000 hours of continuous salt spray with corrosion resistance warranted for 12 months. This is a fundamentally different specification to the Polished Chrome (BL5051MG, external grade) and Satin Chrome (BL5051SC, PVD) variants. Choose Black MG Pro for coastal, beachside, poolside and marine positions; choose Polished Chrome or Satin Chrome for sheltered or interior doors. Background: do you actually need MG Pro? and the honest brand corrosion comparison.
Chrome Variants Not Suitable for Coastal or Saline Environments
The Polished Chrome and Satin Chrome variants are weather resistant for sheltered external use but not rated for coastal, beachside or saltwater-adjacent positions - salt air destroys standard finishes, as documented in our coastal conditions guide. At the coast, select the Black MG Pro variant on this page, or the BL5051MGPROECP for marine grade with on-door code change.
The Polished Chrome and Satin Chrome variants are weather resistant for sheltered external use but not rated for coastal, beachside or saltwater-adjacent positions - salt air destroys standard finishes, as documented in our coastal conditions guide. At the coast, select the Black MG Pro variant on this page, or the BL5051MGPROECP for marine grade with on-door code change.
Corrosion Resistance Warranted - 12 Months
Borg warrants corrosion resistance for 12 months from date of sale under specified conditions - on the Black MG Pro variant that warranty holds even in salt air.
Borg warrants corrosion resistance for 12 months from date of sale under specified conditions - on the Black MG Pro variant that warranty holds even in salt air.
Fire Rated - AS 1905.1-2005
Successfully tested up to 4 hours (depending on the doorset) on fire door assemblies in accordance with AS 1905.1-2005 Fire Resistant Doorsets. Note the egress caution below before specifying on a fire door. Background: fire door types and AS 1905.1 certification and our fire door rated locks category.
Successfully tested up to 4 hours (depending on the doorset) on fire door assemblies in accordance with AS 1905.1-2005 Fire Resistant Doorsets. Note the egress caution below before specifying on a fire door. Background: fire door types and AS 1905.1 certification and our fire door rated locks category.
Code Change Is a Bench Job - Tumbler System, Lock Removal Required
This model uses Borg's tumbler-based code system. To change a PIN, the keypad unit comes off the door and onto the bench: remove the cover plate (4 red screws), hold the C tumbler depressed, and use the supplied tweezers to reposition the red (coded) and blue (uncoded) tumblers. It is a fiddly job the first time - read the bench method step-by-step and the traps to avoid before starting. If codes will change often (rentals, strata, staff turnover), choose the on-door ECP sisters instead: BL5051MGPROECP (marine black) or BL5051MGECP (external chrome).
This model uses Borg's tumbler-based code system. To change a PIN, the keypad unit comes off the door and onto the bench: remove the cover plate (4 red screws), hold the C tumbler depressed, and use the supplied tweezers to reposition the red (coded) and blue (uncoded) tumblers. It is a fiddly job the first time - read the bench method step-by-step and the traps to avoid before starting. If codes will change often (rentals, strata, staff turnover), choose the on-door ECP sisters instead: BL5051MGPROECP (marine black) or BL5051MGECP (external chrome).
Code Required to Exit - No Free Egress From Inside
Full keypads sit on both faces of the door, and the inside lever will not operate until the correct PIN is entered. There is no free-exit lever. Confirm this complies with the fire egress and building regulations for your doorway before purchasing - see exit paths on double-sided locks. If you need free inside egress, choose the single-sided Borg BL5001 - same platform, free-turning inside lever.
Full keypads sit on both faces of the door, and the inside lever will not operate until the correct PIN is entered. There is no free-exit lever. Confirm this complies with the fire egress and building regulations for your doorway before purchasing - see exit paths on double-sided locks. If you need free inside egress, choose the single-sided Borg BL5001 - same platform, free-turning inside lever.
Independent Coding Chambers - Different Codes Each Side
Each keypad has its own mechanical coding chamber. Both sides can share one code, or each side can run a different code - useful where entry is shared but exit is restricted to staff, or vice versa.
Each keypad has its own mechanical coding chamber. Both sides can share one code, or each side can run a different code - useful where entry is shared but exit is restricted to staff, or vice versa.
Free Passage Function (F Button) - Independent Per Side
During busy periods either side can be set to free passage: enter the code, rotate the lever, then press F while the lever is rotated - that side's lever becomes free-turning without needing the code on each use. To return to locked mode, rotate the lever and press C until an audible click is heard. If free passage should never be available, the F tumbler can be removed from that side's coding chamber during a bench code change (a replacement F tumbler is available if it is ever wanted back). More on passage mode vs holdback mode.
During busy periods either side can be set to free passage: enter the code, rotate the lever, then press F while the lever is rotated - that side's lever becomes free-turning without needing the code on each use. To return to locked mode, rotate the lever and press C until an audible click is heard. If free passage should never be available, the F tumbler can be removed from that side's coding chamber during a bench code change (a replacement F tumbler is available if it is ever wanted back). More on passage mode vs holdback mode.
Fully Mechanical - No Batteries Required
Entirely mechanical - no power source, no wiring, no batteries to go flat. Weighing this against an app-connected lock? See mechanical digital vs smart locks and Buyer's Guide Chapter 16.
Entirely mechanical - no power source, no wiring, no batteries to go flat. Weighing this against an app-connected lock? See mechanical digital vs smart locks and Buyer's Guide Chapter 16.
Designed for medium to heavy usage areas
Strengthened clutch and coding chamber on the 5000-series platform, cycle tested past 100,000 operations.
Strengthened clutch and coding chamber on the 5000-series platform, cycle tested past 100,000 operations.
Not suitable for extremely high traffic without a servicing schedule
For maximum heavy duty, consider the Lockwood 3572DX, Borg BL7701, or Carbine CDL7200 - see what heavy duty actually means.
For maximum heavy duty, consider the Lockwood 3572DX, Borg BL7701, or Carbine CDL7200 - see what heavy duty actually means.
Single PIN Code Per Keypad
Each keypad holds one active PIN code at a time (the two sides can differ). No multi-user code list and no audit trail - the honest limitation of every mechanical digital lock; see what these locks will not do.
Each keypad holds one active PIN code at a time (the two sides can differ). No multi-user code list and no audit trail - the honest limitation of every mechanical digital lock; see what these locks will not do.
Access Methods
App / Bluetooth / WiFiBrowse other PIN code locks or the full Digital Mechanical Locks range.
Key Features
- Medium-heavy duty BL5000 series - strengthened clutch and coding chamber; cycle tested to 100,000+ operations.
- Back-to-back keypads and levers - a code is required from both sides; no free inside egress.
- Independent coding chambers - a different code can be set on each side.
- Free passage function per side (F button) - hold either side open during busy periods.
- Three finish variants on this listing: Polished Chrome, Satin Chrome, and Black Marine Grade Pro.
- BL5051MGPRO (Black) - 316 stainless steel internals, MG Pro marine coating, 1,000hr salt spray tested, corrosion warranted 12 months - the coastal choice.
- BL5051MG (Polished Chrome) - external grade, weather resistant, not coastal.
- BL5051SC (Satin Chrome) - PVD finish, sheltered external and internal use.
- Fire rated to AS 1905.1-2005 for use on fire door assemblies (up to 4 hours, doorset dependent).
- Fully mechanical - no batteries, no wiring, no power source.
- Over 1,000 non-sequential code combinations per keypad, entered in any order.
- 60mm anti-thrust stainless steel tubular latch; 70mm and 28mm narrow stile options available separately.
- Soft grip lever handles both sides; clutching action - the lever spins freely without a valid code, so it cannot be forced.
- Door thickness 35mm to 80mm on the standard fixings; up to 85mm with the XL fixing kit.
- Reversible on site for left or right hand doors - no handed ordering.
What's in the Box
- Borg BL5051 outside keypad and lever assembly (selected finish)
- Inside keypad and lever assembly - identical unit (selected finish)
- 60mm heavy duty anti-thrust tubular latch
- Strike plate and box keep
- 2 x spindles (80mm and 90mm)
- M4 fixing screws (40mm, 50mm and 60mm options)
- 4 x 16mm screws
- 2 x coded tumblers (red - spare)
- 2 x non-coded tumblers (blue - spare)
- Tweezers (for code change)
- Hex wrench (Allen key)
- Handle screw rubber grommet
Note: a 70mm backset latch, a 28mm narrow stile latch and the XL fixing kit for 85mm doors are available separately - see Accessories and Spare Parts. No batteries or wiring are required or supplied.
Suitable Uses
- Coastal, beachside, poolside and marine positions - specify the Black MG Pro variant (BL5051MGPRO); see our external gate exposed to rain category.
- Sheltered external doors - Polished Chrome (BL5051MG) or Satin Chrome (BL5051SC).
- Internal commercial, amenities and storeroom doors requiring controlled access from both sides.
- Fire-rated door assemblies on commercial, strata and residential properties - subject to the egress caution above.
- Plant rooms, server rooms and utility areas where access is controlled in both directions and the code rarely changes - if codes change often, the ECP sisters are the better buy.
- Two-zone control - shared entry code on one side, staff-only code on the other, using the independent coding chambers; see when to consider a double-sided lock.
Available Finish Options
All three variants are selected on this page. The finishes are not equal in weather grade - the Black variant carries a fundamentally different marine specification.
Polished Chrome
(This Product)
BL5051MG - external grade, not coastal
Satin Chrome
(This Product)
BL5051SC - PVD, sheltered/internal
Black - Marine Grade Pro
(This Product)
BL5051MGPRO - 316 SS, 1,000hr salt spray
Finish selection does not change the lock's operation, fire rating or dimensions - only the weather grade differs, and only the Black MG Pro variant is coastal rated.
Borg Back-to-Back Lever/Lever Range Compared
Every model below is a back-to-back (BTB) lever/lever - a code is required from both sides, all fully mechanical with no batteries. The differences are the weather grade, the code change method, and whether a key override is fitted.
ECP = Easicode Pro on-door code change. MG Pro = Marine Grade Pro - 316 stainless steel internals, 1,000hr salt spray tested. Combinations are per side on every model.
Related back-to-back formats on the same tumbler platform: the BL5101 knob/knob BTB and the BL5151SC knob/lever hybrid BTB - choose those where a knob is preferred on one or both faces.
Accessories and Spare Parts - 5000 Series
Borg supports the 5000-series platform with a full spare parts catalogue - one of the reasons this range outlasts hardware store imitations. Everything below suits the BL5051.
Spare coded (red) and non-coded (blue) tumblers ship in the box; additional tumbler sets, the 28mm narrow stile latch (BLS275000) and the XL fixing kit for 85mm doors can be ordered through Terry's.
Full Specifications
Dimensions
The BL5051 uses the same BL5000-series keypad body on both faces of the door - the inside unit is identical to the outside unit, not a slim handle plate.
Back-to-back keypad and lever - 177mm H x 48mm W, 26mm body depth, 115mm lever, 89mm total projection. Full-width drawings in the Dimensions tab.
Frequently Asked Questions
How do I change the PIN code on this model?
It is a bench job. Take the keypad unit off the door, remove the cover plate (4 red screws), then with the C tumbler held depressed use the supplied tweezers to lift and reposition the red (coded) and blue (uncoded) tumblers to the new code positions. Refit the plate, test the new code at least five times before rehanging, then repeat on the other side if that code is changing too. The full illustrated procedure is in the bench method guide - and read the traps first: it is genuinely fiddly, and a dropped tumbler is the classic mistake.
It is a bench job. Take the keypad unit off the door, remove the cover plate (4 red screws), then with the C tumbler held depressed use the supplied tweezers to lift and reposition the red (coded) and blue (uncoded) tumblers to the new code positions. Refit the plate, test the new code at least five times before rehanging, then repeat on the other side if that code is changing too. The full illustrated procedure is in the bench method guide - and read the traps first: it is genuinely fiddly, and a dropped tumbler is the classic mistake.
Why does this lock require a code from the inside?
The BL5051 is the back-to-back version of the single-sided BL5001. Where the BL5001's inside lever always turns freely, the BL5051 puts a full keypad on both faces, so access is controlled in both directions - the point of the product on gates and secure rooms, and why single-sided locks fall short on gates. If free egress is required by your building or fire regulations, choose the BL5001 instead.
The BL5051 is the back-to-back version of the single-sided BL5001. Where the BL5001's inside lever always turns freely, the BL5051 puts a full keypad on both faces, so access is controlled in both directions - the point of the product on gates and secure rooms, and why single-sided locks fall short on gates. If free egress is required by your building or fire regulations, choose the BL5001 instead.
Why is the Black MG Pro variant better than the chrome variants for coastal use?
BL5051MGPRO uses 316 stainless steel internal components and MG Pro black marine coating, tested to 1,000 hours of continuous salt spray - roughly four times the exposure of standard external-grade testing. The Polished Chrome and Satin Chrome variants use external grade and PVD decorative finishes designed for normal weather only; in salt air those finishes corrode. The decode is at salt spray ratings explained.
BL5051MGPRO uses 316 stainless steel internal components and MG Pro black marine coating, tested to 1,000 hours of continuous salt spray - roughly four times the exposure of standard external-grade testing. The Polished Chrome and Satin Chrome variants use external grade and PVD decorative finishes designed for normal weather only; in salt air those finishes corrode. The decode is at salt spray ratings explained.
Can each side have a different code?
Yes. Each keypad has its own independent coding chamber. Both sides can share one code, or each can be set to a completely different code during the bench procedure. The free passage function is also engaged and released per side.
Yes. Each keypad has its own independent coding chamber. Both sides can share one code, or each can be set to a completely different code during the bench procedure. The free passage function is also engaged and released per side.
Can I reverse the handing on site?
Yes. All BL5051 units ship factory set for right-hand doors. To change to left-hand: remove the rubber grommet at the base of each keypad handle, use the included hex wrench to remove the grub screw, rotate the handle 180 degrees and refit. Handing is determined from the outside of the door - right hand means hinges on the right, left hand means hinges on the left, regardless of swing direction. Background: understanding door handing in Australia.
Yes. All BL5051 units ship factory set for right-hand doors. To change to left-hand: remove the rubber grommet at the base of each keypad handle, use the included hex wrench to remove the grub screw, rotate the handle 180 degrees and refit. Handing is determined from the outside of the door - right hand means hinges on the right, left hand means hinges on the left, regardless of swing direction. Background: understanding door handing in Australia.
Additional Information
Set the Codes Before Installation:
The tumbler system can be coded with the lock on or off the door, but the bench is far easier. Set and verify both side codes before mounting - know the current code, work with the door open, and test five times per side. That avoids removing a fitted lock for the first code change.
The tumbler system can be coded with the lock on or off the door, but the bench is far easier. Set and verify both side codes before mounting - know the current code, work with the door open, and test five times per side. That avoids removing a fitted lock for the first code change.
Black MG Pro Marine Maintenance:
Monthly - a light spray of silicon-based lubricant (GT85 or equivalent) over both keypads and levers, excess wiped off; never oil-based products. Annually - remove the lock, spray internally through the button holes, and test every button and both levers. The routine is in the Borg Servicing Guide (PDF); Terry's can also handle it on a schedule - see advice and installation.
Monthly - a light spray of silicon-based lubricant (GT85 or equivalent) over both keypads and levers, excess wiped off; never oil-based products. Annually - remove the lock, spray internally through the button holes, and test every button and both levers. The routine is in the Borg Servicing Guide (PDF); Terry's can also handle it on a schedule - see advice and installation.
Fire Door Installations:
When specifying for a fire door, confirm every other item of hardware in the assembly is fire rated and compatible with the doorset certification - the rating depends on the doorset tested. And confirm the code-to-exit arrangement complies with the emergency egress requirements for that doorway before ordering; see what is actually compliant on apartment fire doors.
When specifying for a fire door, confirm every other item of hardware in the assembly is fire rated and compatible with the doorset certification - the rating depends on the doorset tested. And confirm the code-to-exit arrangement complies with the emergency egress requirements for that doorway before ordering; see what is actually compliant on apartment fire doors.
Retrofitting a Lockwood 3572 Mortice:
If the door already carries a Lockwood 3572 mortice lock, the BL50013572KBTB back-to-back adaptor kit mounts both 5000-series keypad units straight onto the existing mortice prep - no re-boring the door for the tubular latch.
If the door already carries a Lockwood 3572 mortice lock, the BL50013572KBTB back-to-back adaptor kit mounts both 5000-series keypad units straight onto the existing mortice prep - no re-boring the door for the tubular latch.
Change Codes Often? Buy the ECP Version Instead:
The tumbler bench method is fine for a set-and-forget code. If your site retires codes regularly - holiday rentals, strata, staff turnover - the on-door Easicode Pro sisters turn a bench job into a 30-second key turn: BL5051MGPROECP (marine black) or BL5051MGECP (external chrome). The trade-off is explained at why ECP matters and how long each method really takes.
The tumbler bench method is fine for a set-and-forget code. If your site retires codes regularly - holiday rentals, strata, staff turnover - the on-door Easicode Pro sisters turn a bench job into a 30-second key turn: BL5051MGPROECP (marine black) or BL5051MGECP (external chrome). The trade-off is explained at why ECP matters and how long each method really takes.
Warranty
Borg Locks Warranty - 12 Months (Australia)
All Borg locks are warranted against mechanical defects in materials and workmanship under normal use and service for a minimum of 12 months from date of sale. Corrosion resistance is also warranted for 12 months under specified conditions. The warranty does not cover damage arising from misuse, vandalism, or improper installation, and the lock must not be dismantled beyond the documented code change procedure.
All Borg locks are warranted against mechanical defects in materials and workmanship under normal use and service for a minimum of 12 months from date of sale. Corrosion resistance is also warranted for 12 months under specified conditions. The warranty does not cover damage arising from misuse, vandalism, or improper installation, and the lock must not be dismantled beyond the documented code change procedure.
Purchased through Terry's Locksmiths? Contact Terry's Locksmiths first - we'll manage your warranty claim on your behalf. This warranty operates alongside your rights under the Australian Consumer Law.
PDF Downloads
Borg BL5051 - FAQ, Setup and Owner's Guide
Everything below is here to help you choose a variant, install, code and live with the BL5051 back-to-back tumbler lock. For the wider category, start with Buyer's Guide Chapter 16 - Mechanical Digital Locks and the pillar explainer What Is a Mechanical Digital Lock?
Codes and Code Changing
How does the code entry actually work - is it like a phone keypad?
Not quite. This is a purely mechanical coding chamber: each keypad holds one code, and the digits are pressed in any order - the chamber only cares that the correct set of buttons is depressed. Press C first to clear any half-entered attempt, enter the code, then turn the lever. Each digit can be used once per code.
Not quite. This is a purely mechanical coding chamber: each keypad holds one code, and the digits are pressed in any order - the chamber only cares that the correct set of buttons is depressed. Press C first to clear any half-entered attempt, enter the code, then turn the lever. Each digit can be used once per code.
How long does a tumbler code change really take?
Allow 15-20 minutes per side the first time, including removal and refitting - and considerably less once you have done it twice. The steps: keypad off the door, cover plate off (4 red screws), C tumbler held depressed, tweezers to move the red (coded) and blue (uncoded) tumblers into the new pattern, plate back on, five successful tests, then rehang. The honest time comparison across all Borg methods is at how long code changes take, and the method itself at the Borg standard tumbler system.
Allow 15-20 minutes per side the first time, including removal and refitting - and considerably less once you have done it twice. The steps: keypad off the door, cover plate off (4 red screws), C tumbler held depressed, tweezers to move the red (coded) and blue (uncoded) tumblers into the new pattern, plate back on, five successful tests, then rehang. The honest time comparison across all Borg methods is at how long code changes take, and the method itself at the Borg standard tumbler system.
What are the classic tumbler code change mistakes?
Dropping a tumbler (work over a tray), losing track of which tumblers came out of which slots, coding the two sides differently by accident when they were meant to match, and rehanging without testing. The rules that prevent a lockout: know the current code before you start, work with the door open, and test five times per side. The full trap list is at bench method traps.
Dropping a tumbler (work over a tray), losing track of which tumblers came out of which slots, coding the two sides differently by accident when they were meant to match, and rehanging without testing. The rules that prevent a lockout: know the current code before you start, work with the door open, and test five times per side. The full trap list is at bench method traps.
What are the spare red and blue tumblers in the box for?
Red tumblers are coded (button becomes part of the PIN), blue are uncoded. The spares let you lengthen or shorten a code - a longer PIN uses more red tumblers. Additional tumbler sets are available through Terry's, and the free-passage F tumbler is sold separately if one is removed or lost - see spare tumblers explained.
Red tumblers are coded (button becomes part of the PIN), blue are uncoded. The spares let you lengthen or shorten a code - a longer PIN uses more red tumblers. Additional tumbler sets are available through Terry's, and the free-passage F tumbler is sold separately if one is removed or lost - see spare tumblers explained.
What happens if the code is forgotten - is there a key backup?
No - there is no key override on this model, which also means no cylinder to pick or corrode. With the door open, the code can be read from the tumbler pattern on the bench. With the door locked it is a locksmith visit. If site policy requires a keyed bypass, the BL5771MGPROECP is the BTB with keyed override on both faces.
No - there is no key override on this model, which also means no cylinder to pick or corrode. With the door open, the code can be read from the tumbler pattern on the bench. With the door locked it is a locksmith visit. If site policy requires a keyed bypass, the BL5771MGPROECP is the BTB with keyed override on both faces.
Can multiple people have their own codes, and is there a record of who came through?
No - one active code per keypad, no user list, no audit trail. That is the honest trade-off of every mechanical digital lock against an app-based system: see what these locks will not do and mechanical vs smart compared.
No - one active code per keypad, no user list, no audit trail. That is the honest trade-off of every mechanical digital lock against an app-based system: see what these locks will not do and mechanical vs smart compared.
Choosing Your Variant
Which variant do I choose - Polished Chrome, Satin Chrome or Black MG Pro?
Decide by exposure, not colour. Anywhere within reach of salt air - beachfront, canal estates, poolside, marinas - the Black MG Pro is the only variant warranted to survive: 316 SS internals and 1,000hr salt spray coating. Sheltered external doors (under cover, away from the coast) suit the Polished Chrome; internal and lightly sheltered doors suit the Satin Chrome PVD. When in doubt on the Gold Coast, buy the MG Pro - the guide is do you actually need MG Pro?
Decide by exposure, not colour. Anywhere within reach of salt air - beachfront, canal estates, poolside, marinas - the Black MG Pro is the only variant warranted to survive: 316 SS internals and 1,000hr salt spray coating. Sheltered external doors (under cover, away from the coast) suit the Polished Chrome; internal and lightly sheltered doors suit the Satin Chrome PVD. When in doubt on the Gold Coast, buy the MG Pro - the guide is do you actually need MG Pro?
What does 1,000 hours of salt spray actually prove?
Salt spray testing runs the hardware in a continuous saline fog chamber. Standard external-grade finishes are typically tested to around 240 hours; MG Pro runs to 1,000 continuous hours - roughly four times the exposure - with 316 stainless steel internals behind the coating. Full decode: salt spray ratings and MG Pro explained.
Salt spray testing runs the hardware in a continuous saline fog chamber. Standard external-grade finishes are typically tested to around 240 hours; MG Pro runs to 1,000 continuous hours - roughly four times the exposure - with 316 stainless steel internals behind the coating. Full decode: salt spray ratings and MG Pro explained.
Why choose a mechanical lock over a smart lock at the coast?
Electronics and salt air are a poor mix - corroded battery terminals, failed keypads and dead boards are the common coastal failure modes documented in the realities of electronic door locks. A fully mechanical MG Pro lock removes every one of those failure paths, and the brand comparison shows why Borg's marine tier leads here.
Electronics and salt air are a poor mix - corroded battery terminals, failed keypads and dead boards are the common coastal failure modes documented in the realities of electronic door locks. A fully mechanical MG Pro lock removes every one of those failure paths, and the brand comparison shows why Borg's marine tier leads here.
What maintenance keeps the corrosion warranty intact?
A monthly light spray of silicon-based lubricant (GT85 or equivalent) over the keypads and levers, wiped of excess, and an annual internal spray through the button holes with a full button-and-lever test. Never oil-based products. The routine is set out in the Borg Servicing Guide - ten minutes a month on a beachfront gate.
A monthly light spray of silicon-based lubricant (GT85 or equivalent) over the keypads and levers, wiped of excess, and an annual internal spray through the button holes with a full button-and-lever test. Never oil-based products. The routine is set out in the Borg Servicing Guide - ten minutes a month on a beachfront gate.
Fit and Installation
What latch do I need for a narrow gate frame?
The standard 60mm-backset tubular latch runs about 80mm behind the faceplate and fits comfortably in a 100x50mm frame. For narrower stiles Borg makes a 28mm-backset narrow stile latch (BLS275000) - contact Terry's to add one to your order. Measure first: gate post too narrow for a 60mm latch?
The standard 60mm-backset tubular latch runs about 80mm behind the faceplate and fits comfortably in a 100x50mm frame. For narrower stiles Borg makes a 28mm-backset narrow stile latch (BLS275000) - contact Terry's to add one to your order. Measure first: gate post too narrow for a 60mm latch?
Can I get a 70mm backset, and in which finish?
Yes - in satin chrome via the BLL500070, and in black marine grade via the BLSMGPRO570 MG Pro tube latch - the correct choice on a Black MG Pro coastal installation so the latch matches the lock's corrosion tier.
Yes - in satin chrome via the BLL500070, and in black marine grade via the BLSMGPRO570 MG Pro tube latch - the correct choice on a Black MG Pro coastal installation so the latch matches the lock's corrosion tier.
Which spindle do I use for my door thickness?
Two spindles are supplied (80mm and 90mm). The rule: door thickness + 30mm = minimum spindle length, because 15mm must seat into each keypad body. A 50mm door needs at least an 80mm spindle. Use the longest that fits, and if cutting is needed, cut from the inside handle end only.
Two spindles are supplied (80mm and 90mm). The rule: door thickness + 30mm = minimum spindle length, because 15mm must seat into each keypad body. A 50mm door needs at least an 80mm spindle. Use the longest that fits, and if cutting is needed, cut from the inside handle end only.
The door already has a Lockwood 3572 mortice - can this lock go straight on?
Yes, with the BL50013572KBTB back-to-back adaptor kit - it mounts both 5000-series keypad units onto the existing 3572 mortice prep, driving the mortice instead of a tubular latch. For open-out doors on the short-backset Lockwood 3582 prep, use the BL50013582K kit. This retrofit ecosystem is a key advantage over hardware store lookalikes.
Yes, with the BL50013572KBTB back-to-back adaptor kit - it mounts both 5000-series keypad units onto the existing 3572 mortice prep, driving the mortice instead of a tubular latch. For open-out doors on the short-backset Lockwood 3582 prep, use the BL50013582K kit. This retrofit ecosystem is a key advantage over hardware store lookalikes.
Is a code-to-exit lock allowed on a fire door?
The lock is fire rated to AS 1905.1-2005 (up to 4 hours, doorset dependent) - but fire rating and egress compliance are separate questions. Many exit paths require an unimpeded single-action exit, which a back-to-back keypad does not provide. Confirm the specific doorway's egress requirement with your certifier before ordering; see exit paths, fire door certification, and why passage functions are not a fire-door fix.
The lock is fire rated to AS 1905.1-2005 (up to 4 hours, doorset dependent) - but fire rating and egress compliance are separate questions. Many exit paths require an unimpeded single-action exit, which a back-to-back keypad does not provide. Confirm the specific doorway's egress requirement with your certifier before ordering; see exit paths, fire door certification, and why passage functions are not a fire-door fix.
Is a latch lock right for a pool gate?
A spring latch self-latches when the gate swings shut - the behaviour pool fencing needs - where a deadbolt relies on someone remembering to throw it. The format decision is covered at self-latching explained and pool gate requirements - and remember free passage mode must never be engaged on a pool gate; see why holdback and pool gates do not mix.
A spring latch self-latches when the gate swings shut - the behaviour pool fencing needs - where a deadbolt relies on someone remembering to throw it. The format decision is covered at self-latching explained and pool gate requirements - and remember free passage mode must never be engaged on a pool gate; see why holdback and pool gates do not mix.
Range and Spares
BL5051MG, BL5051SC, BL5051MGPRO - what do the suffixes mean?
Borg's naming stacks the designations: MG = external weather grade, SC = satin chrome, MG Pro = marine grade (316 SS + 1,000hr salt spray), and an ECP suffix adds Easicode Pro on-door code change. The three variants on this page are all tumbler code change; add ECP and you get the BL5051MGECP and BL5051MGPROECP standalone listings.
Borg's naming stacks the designations: MG = external weather grade, SC = satin chrome, MG Pro = marine grade (316 SS + 1,000hr salt spray), and an ECP suffix adds Easicode Pro on-door code change. The three variants on this page are all tumbler code change; add ECP and you get the BL5051MGECP and BL5051MGPROECP standalone listings.
I want a knob instead of a lever on one or both sides - is there a BTB for that?
Yes - the same tumbler BTB platform comes as the BL5101 knob/knob and the BL5151SC knob/lever hybrid. Note that knobs are harder to operate with full hands or limited grip - the lever remains the accessible choice.
Yes - the same tumbler BTB platform comes as the BL5101 knob/knob and the BL5151SC knob/lever hybrid. Note that knobs are harder to operate with full hands or limited grip - the lever remains the accessible choice.
Which parts are actually replaceable if something wears?
Almost everything: the keypad unit itself, the latches, the spring pack, the weather gaskets and the F tumbler - see the full Accessories and Spare Parts table. This spare-parts depth is a core reason to buy a supported platform over a hardware store lookalike - and the build quality gap is real.
Almost everything: the keypad unit itself, the latches, the spring pack, the weather gaskets and the F tumbler - see the full Accessories and Spare Parts table. This spare-parts depth is a core reason to buy a supported platform over a hardware store lookalike - and the build quality gap is real.
Is this heavy duty enough for a busy commercial doorway?
It is a medium-heavy duty lock, cycle tested past 100,000 operations - ample for gates, plant rooms and staff doors. For genuinely relentless traffic (schools, hospitals, main-entry commercial), step up to a true heavy-duty platform: the Borg BL7701, Lockwood 3572DX or the dual-keypad Carbine CDL7200 KDSC - the cross-brand back-to-back equivalent. Guidance at Ch 16 commercial use.
It is a medium-heavy duty lock, cycle tested past 100,000 operations - ample for gates, plant rooms and staff doors. For genuinely relentless traffic (schools, hospitals, main-entry commercial), step up to a true heavy-duty platform: the Borg BL7701, Lockwood 3572DX or the dual-keypad Carbine CDL7200 KDSC - the cross-brand back-to-back equivalent. Guidance at Ch 16 commercial use.
Related Products, Guides and Chapters
This lock and its siblings: BL5051MGECP - External Grade ECP Chrome · BL5051MGPROECP - Marine ECP Black · BL5771MGPROECP - BTB with Key Override · BL5001 - Single-Sided, Free Egress · BL5101 - Knob/Knob BTB · BL5151SC - Knob/Lever BTB
Accessories and spares: F Tumbler · MG Pro Tube Latch 60/70mm Black · Spare Lever Keypad · Black Scar Plates · 3572 BTB Adaptor Kit · Spring Accessories Packet
Cross-brand alternatives: Carbine CDL7200 KDSC Dual Keypad · Lockwood 3572DX · Borg BL7701 Heavy Duty · Carbine CDL7200 Dual Lever
Buyer's Guide chapters: Ch 16 Mechanical Digital Locks · Ch 16 Borg Naming Decoded · Ch 16 Code Changing Methods · Ch 16 Choosing a Model
Helpful blog reading: Changing Codes - The Bench Method · MG Pro & ECP Explained · Why Double-Sided Locks Suit Gates · Lockwood vs Borg vs Carbine · Heavy Duty Commercial Mech-Digi · Latch vs Bolt Formats · The Realities of Electronic Door Locks · Why Our Range Beats Imitations
What's In The Box - Borg BL5051 (MG / SC / MGPRO)
- Borg BL5051 outside keypad and lever assembly (selected finish)
- Inside keypad and lever assembly - identical unit (selected finish)
- 60mm heavy duty anti-thrust tubular latch
- Strike plate and box keep
- 2 x spindles (80mm and 90mm)
- M4 fixing screws (40mm, 50mm and 60mm options)
- 4 x 16mm screws
- 2 x coded tumblers (red - spare)
- 2 x non-coded tumblers (blue - spare)
- Tweezers (for code change)
- Hex wrench (Allen key)
- Handle screw rubber grommet
Note: the Black MG Pro variant (BL5051MGPRO) is built with marine grade 316 SS components; the Polished Chrome and Satin Chrome variants use external grade and PVD components. The box contents are otherwise identical across all three. A 70mm backset latch, a 28mm narrow stile latch (BLS275000) and the XL fixing kit for 85mm doors are available separately. No batteries or wiring are required or supplied.
Borg 5000 Series - Real Installations
Installed by Terry's - Mermaid Beach QLD
Installed by Terry's - Southport QLD
Installed by Terry's - Robina QLD
Installed by Terry's - Broadbeach QLD
Installed by Terry's - Southport QLD
Installed by Terry's - Burleigh Heads QLD
Installed by Terry's - Robina QLD
Installed by Terry's - Varsity Lakes QLD
Installed by Terry's - Nerang QLD
Installed by Terry's - Helensvale QLD
Installed by Terry's - Palm Beach QLD
Installed by Terry's - Coomera QLD
Installed by Terry's - Labrador QLD
Borg BL5051 - Dimensions
On this back-to-back model the inside unit is the same BL5000-series keypad body as the outside unit - both faces measure identically. Dimensions apply to all three finish variants.
Back-to-back keypad and lever drawing: keypad body 177mm high x 48mm wide, 26mm body depth from the door face, 115mm lever, 89mm total projection including the lever. These are the figures used in the dimensions table on the Description tab.
Manufacturer isometric drawing of the BL5000 keypad unit - shown as external and internal keypad because the same unit sits on both faces of a back-to-back installation. Figures per this drawing: 178mm high x 48mm wide, 26mm door-face depth, 72mm depth, 129.4mm lever.
Standard 60mm backset (70mm and 28mm narrow stile latches available separately). Fixings suit doors 35-80mm on the standard kit; up to 85mm with the XL fixing kit.
Borg BL5000 Series - Product Brochure
BL5000 Series - full model range, handle styles, fire tested variants and all dimensions
Borg Locks Warranty
Borg products sold in Australia are covered against mechanical defects in materials and workmanship under normal use and service. Warranty claims are handled by Terry's Tradies Pty Ltd and its associated websites, trading names, and subsidiaries.
Warranty Summary
What the Warranty Covers
- Mechanical defects in materials and workmanship
- Defects arising under normal use and service conditions
- Repair or replacement of defective units at the discretion of the Australian distributor (LSC)
What the Warranty Does Not Cover
- Damage arising from misuse, vandalism, or abuse
- Damage resulting from improper installation
- Locks that have been dismantled - dismantling invalidates the warranty
- Normal wear and tear
- Cosmetic damage not affecting function
How to Make a Claim
For full returns and warranty claim procedures, visit our Returns & Warranty page - this is kept up to date and is the authoritative reference for current claim steps.
- Contact Terry's Tradies Pty Ltd first if you purchased through us or one of its associated trading names - we will assess the issue and manage the warranty process with LSC on your behalf. You do not need to contact LSC or Borg Locks UK directly.
- Have your proof of purchase ready (receipt or order confirmation).
- Warranty claims for Borg products in Australia are processed through LSC, the authorised Australian importer and distributor. Where an item is returned to LSC, freight charges must be prepaid and the item returned within the warranty period.
- If LSC finds the returned item to be defective, it will be repaired or replaced, and a detailed assessment report is provided to the customer after examination.
Australian Consumer Law
Our goods come with guarantees that cannot be excluded under the Australian Consumer Law. You are entitled to a replacement or refund for a major failure and compensation for any other reasonably foreseeable loss or damage. You are also entitled to have the goods repaired or replaced if the goods fail to be of acceptable quality and the failure does not amount to a major failure. The Borg manufacturer warranty above operates alongside - and does not limit - these statutory rights.
Our goods come with guarantees that cannot be excluded under the Australian Consumer Law. You are entitled to a replacement or refund for a major failure and compensation for any other reasonably foreseeable loss or damage. You are also entitled to have the goods repaired or replaced if the goods fail to be of acceptable quality and the failure does not amount to a major failure. The Borg manufacturer warranty above operates alongside - and does not limit - these statutory rights.
Confused? Overwhelmed? We get it.
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