Borg BL2620MGBC Mechanical Digital Lock – Knob/Knob Back-to-Back – External Grade – Polished Chrome
At A Glance
The Borg BL2620MGBC is a fully mechanical digital lock in a knob/knob back-to-back (BTB) configuration with an external grade polished chrome finish. Both sides of the door carry an identical knob keypad — the correct PIN must be entered to operate the knob from either side, so there is no free inside egress.
The external series finish uses layers of polished chrome plating over 316 grade stainless steel internal components, warranted to resist corrosion for 12 months in normal weather conditions. That makes it suited to sheltered external doors and general external-grade applications, but it is not rated for coastal or saline environments — for a knob/knob back-to-back lock built for that exposure, see the Borg BL2621 MG Pro ECP.
Fully mechanical — no batteries, no wiring, no power source of any kind. Suits doors from 35mm to 80mm thick. Code changing uses the traditional Borg tumbler system: the lock comes off the door, the cover plate lifts to expose the coding chamber, and red (coded) and blue (uncoded) tumblers are repositioned with the supplied tweezers. Over 1,000 non-sequential combinations are available.
Usually same day if ordered before 11am AEST (excluding weekends and Qld public holidays)
The BL2620MGBC has a knob keypad on both sides of the door. Both knobs are clutched — free-turning only after the correct PIN is entered — and the same code operates both sides. There is no free inside egress: the correct code must be entered from whichever side you are on. Confirm this suits your application before purchasing; if free egress from inside is required, a single-sided Borg 2000/2600 series knob lock is the better fit. A back-to-back keypad also means a single lock can control two rooms or an internal/external pair from one code — see Why Double-Sided Locks Are a Smart Choice for the general case for BTB keypads.
The BL2620MGBC uses an external grade polished chrome finish — not the Marine Grade Pro coating. It is warranted for corrosion resistance in normal weather conditions only. Do not specify this lock for coastal, beachside, poolside, or salt-laden environments. For marine grade construction in the same knob/knob back-to-back format, see the Borg BL2621 MG Pro ECP. MG Pro & ECP Explained covers the difference in salt-spray testing between the two grades.
Polished chrome finish over 316 grade stainless steel internal components. Warranted to resist corrosion in normal weather conditions for 12 months from date of sale. Not suitable for coastal or saline environments.
This model uses a tumbler-based code system, changed on the bench rather than on the door. Remove the lock, take out the 4 red retaining screws, carefully lift the cover plate (springs stay attached), hold the C tumbler depressed throughout, and use the supplied tweezers to reposition the red (coded) and blue (uncoded) tumblers — square cut-outs facing outward, coloured marks facing upward. Over 1,000 non-sequential combinations; spare tumblers let you shorten the code to 3–4 digits or lengthen it to 6–7 digits. See Changing Codes on Mechanical Digital Locks for the general bench-method walkthrough and realistic timing.
The BL2620MGBC includes a holdback facility. Once a knob has been turned to retract the latch, holdback can be engaged to keep that knob (and latch) retracted — allowing free passage on that side without code entry. Turn the knob to release. Useful when the door needs to stay open for extended periods, such as during a delivery or a busy trading window. See Passage Mode vs Holdback Mode for how holdback compares with full passage mode.
Entirely mechanical. No power source, no wiring, and no battery maintenance at any point in the product's life.
For heavy duty: consider the Lockwood 3572DX, the Borg BL7701, or the Carbine CDL7200LL.
Accepts one active PIN code at a time. The same code operates both sides.
The inside knob requires the correct PIN before it will retract the latch. Confirm this suits your application and complies with any applicable fire egress or building regulations before purchasing.
Key Features
- Knob keypad on both sides – code required to enter and exit.
- External grade polished chrome finish over 316 grade stainless steel internal components.
- Corrosion resistance warranted 12 months under normal weather conditions.
- Not suitable for coastal or saline environments.
- Over 1,000 non-sequential code combinations; tumbler code system, changed on the bench.
- Holdback facility – latch can be held retracted on either side for free passage.
- Both knobs clutched – free-turning only once the correct code is entered.
- Fully mechanical – no batteries, no wiring, no power source.
- 60mm anti-thrust stainless steel tubular latch.
- 8mm square drive spindle – compatible with most leading lock brands.
- Suits doors from 35mm to 80mm thick.
- Fully reversible for left or right hand doors.
- 14-button keypad with large indented buttons on both sides.
Access Methods
What's in the Box
- Borg BL2620MGBC outside knob keypad assembly (polished chrome)
- Borg BL2620MGBC inside knob keypad assembly (polished chrome)
- 60mm anti-thrust stainless steel tubular latch
- Strike plate and box keep
- Spindles (to suit door thickness 35–80mm)
- M4 fixing screws
- 2 × coded tumblers (red – spare)
- 2 × non-coded tumblers (blue – spare)
- Tweezers (for tumbler code change)
- Hex wrench (Allen key)
- Handle screw rubber grommet × 2
Suitable Uses
- Internal and sheltered external doors requiring code access control from both sides
- Office, strata, storage, and amenity doors where both-sided code entry is required without free inside egress
- Applications where a polished chrome external-grade finish suits the door and building aesthetic
- Sheltered external doors in normal (non-coastal) weather conditions requiring back-to-back code access
- Doors between 35mm and 80mm thick where a back-to-back knob keypad format is preferred
Browse the full Digital Mechanical Locks range for other Borg, Lockwood, and Carbine mechanical digital options.
Available Finish Options
Polished Chrome
(This Product)
STK BL2620MGBC
Finish selection does not affect functionality, compliance, or performance.
Item Code Family
BL2600MGBC is the single-sided version of this platform – a free-turning inside lever means no code is needed to exit. BL2621 MG Pro ECP is the marine-grade, on-door-code-change counterpart in the same back-to-back format as this product.
Accessories & Spares
Spare coded and non-coded tumblers, and a spare spindle sized specifically for the external-grade BL2600 series, are not currently catalogued as standalone GCSL listings — get in touch with Terry's Locksmiths if you need spares beyond the tumblers already supplied in the box.
Full Specifications
Dimensions
Frequently Asked Questions
No. The BL2620MGBC is an external grade lock, not Marine Grade Pro. It uses a polished chrome finish over 316 stainless steel internal components, warranted to resist corrosion in normal weather conditions for 12 months. It is not suitable for coastal, beachside, poolside, or saline environments. For a marine-grade lock in the same knob/knob back-to-back format, see the Borg BL2621 MG Pro ECP — MG Pro & ECP Explained covers the salt-spray testing difference between the two grades.
No. The BL2620MGBC has knob keypads on both sides. Both knobs are clutched and require the correct PIN to retract the latch, so there is no free inside egress. If you need free egress from inside, the single-sided Borg BL2600MGBC uses a free-turning inside lever instead. Confirm code-required-both-sides suits your application and complies with any applicable fire egress requirements before purchasing.
Holdback lets you keep the latch bolt retracted on a given side, so that side of the door can open and close freely without entering the code each time. To engage: enter the code, turn the knob to retract the latch, then hold the knob in the retracted position to engage holdback (this can be set independently on each side). To exit holdback, turn the knob to release. Useful during periods of high through-traffic when repeated code entry is inconvenient — see Passage Mode vs Holdback Mode for how this compares with full passage mode on other Borg models.
The lock has to come off the door. Remove the 4 red screws, carefully lift the cover plate (springs stay attached), hold the C tumbler depressed throughout, then use the supplied tweezers to reposition the red (coded) and blue (uncoded) tumblers — square cut-outs facing outward, coloured marks facing upward. Test the new code before reinstalling. There are over 1,000 non-sequential combinations, and the code can be entered in any order. Spare tumblers let you shorten the code to 3–4 digits or lengthen it to 6–7 digits. See Changing Codes on Mechanical Digital Locks for the general walkthrough and realistic timing.
The BL2620MGBC suits doors from 35mm to 80mm thick using the spindles supplied. The BL2600MGBC is the single-sided version of this same platform – a knob keypad outside with a free-turning stub lever inside, so no code is needed to exit. Choose BL2620MGBC where code control in both directions is required; choose BL2600MGBC where free inside egress is needed.
Additional Information
This lock is not rated for coastal or saline use. The polished chrome external grade finish will corrode in environments with airborne salt, high humidity, poolside chemicals, or direct saltwater exposure. For any installation near the ocean, a canal, a pool using salt chlorination, or a beachside location, specify the Borg BL2621 MG Pro ECP instead. Fitting an external grade lock in a marine environment will void the corrosion warranty. Lockwood vs Borg vs Carbine has an honest brand-by-brand corrosion comparison if you're weighing grades.
The tumbler code can be set on the bench before installation. Set and verify both sides' codes before mounting. This avoids removing a fitted keypad for the first code change and lets you confirm both sides work correctly before the lock goes into the door. A qualified locksmith can also carry this out for you — see Advice and Installation.
Select the spindle length based on door thickness. General rule: door thickness + 30mm = minimum spindle length (15mm must seat into each keypad). For a 44mm door, use a minimum 74mm spindle. Do not cut the spindle shorter than necessary — an undersized spindle may disengage if the door is slammed.
This page states over 1,000 code combinations, sourced from the Borg drilling template covering the BL2600–BL2700 series specifically. An older version of this listing quoted "over 8,000" without a matching source document — that figure has not been carried forward.
Each side of this lock uses the same external-grade knob keypad, sold separately as the Borg BL2600KMG. If one side is damaged, you do not need to replace the whole lock — order a single replacement keypad for that side.
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. The warranty does not cover damage arising from misuse, vandalism, or improper installation. The lock must not be dismantled — doing so will invalidate the warranty.
Download PDF Resources
Step-by-step tumbler code-changing procedure – remove the cover plate, reposition red and blue tumblers with the supplied tweezers.
Tubular latch installation guide for the BL2600 series – strike plate, drilling, spindle, and keypad/handle fitting.
Fold-along drilling template plus the parts list and tumbler code-change procedure this page's combinations figure is sourced from.
General maintenance guide for Borg mechanical pushbutton keypad locks.
Borg BL2620MGBC – FAQ, Setup and Owner's Guide
Deeper questions on access, security, code changing, and suitability for the Borg BL2620MGBC. For a wider comparison across mechanical digital brands, see the Buyer's Guide's Mechanical Digital Locks chapter.
Access & Credentials
Yes. The BL2620MGBC stores a single PIN, and that one code operates the outside knob keypad and the inside knob keypad identically. It does not support two different codes for the two sides.
Over 1,000 non-sequential combinations, per Borg's own drilling template documentation for the BL2600–BL2700 series. The code can be entered in any order — it is not required to be pressed sequentially.
No. The BL2620MGBC has no mechanical key override on either side — access depends entirely on the correct PIN. If you need a backup key-based entry method, a Borg model with key override (such as the BL7701) or keeping the code recorded securely off-site is the alternative.
Locking & Safety
Confirm this against your local fire and egress regulations before specifying. Because both sides of the BL2620MGBC require a code to operate, it does not provide free-turning exit without code entry — a requirement on many fire door and designated exit-path applications. Where free egress is mandatory, a single-sided model with a free-turning inside lever, such as the Borg BL2600MGBC, is the more appropriate choice.
Both knobs are clutched, meaning they spin freely without engaging the latch until the correct code is entered — this is the standard Borg anti-manipulation design across the mechanical digital range. As with any mechanical keypad lock, physical security also depends on correct installation, door and frame condition, and the strike/latch fit; see the installation PDFs in the PDF Files tab.
Weather & Finish
External Grade (this product) uses polished chrome plating over 316 stainless steel internals, warranted for 12 months of corrosion resistance in normal weather — suited to sheltered external and internal doors, not coastal exposure. Marine Grade Pro uses the MG Pro 2 coating and is salt-spray tested for coastal, beachside, and poolside use. MG Pro & ECP Explained covers the testing standards behind both grades in detail.
Yes, on this specific knob/knob back-to-back external grade listing. Other finishes and grades exist elsewhere in the BL2600 platform — satin chrome on the single-sided BL2600MGBC, and black MG Pro 2 on the marine-grade BL2621 MG Pro ECP.
Installation & Setup
A standard drill with the hole sizes shown in the drilling template PDF, a hex/Allen key (supplied), a screwdriver, and the tweezers supplied for the code change. Most DIY-competent installers can fit this lock in under an hour on a pre-prepared door; drilling a new door from scratch takes longer. If you'd rather not, Advice and Installation covers professional installation options.
No. The BL2620MGBC is fully reversible on site for left or right hand doors — there is no handed-specific ordering required, unlike some hook-bolt or deadbolt models in the wider Borg range.
Suitability
Yes — this is one of the more common genuine uses for a back-to-back knob keypad: an internal or sheltered gate, storage room, or plant room where you want the same code to control access from both directions without issuing separate keys. See Why Double-Sided Locks Are a Smart Choice for the general case.
No. This is a light-to-medium duty lock rated for internal and sheltered external doors, not high-traffic commercial entries. For that application, look at the Lockwood 3572DX, the Borg BL7701, or the Carbine CDL7200LL — the Heavy Duty Commercial Mechanical Digital Locks guide explains what separates commercial-grade from residential mechanical digital locks.
Related Products, Guides and Chapters
- Borg BL2600MGBC – the single-sided version of this platform, free inside egress
- Borg BL2621 MG Pro ECP – marine grade, on-door code change, same back-to-back format
- Borg BL2600KMG – spare knob keypad, external grade, chrome plated
- Borg BL2600MGC – keypad cover, suits 2600 series external grade
- Full Borg Locks range
- Digital Mechanical Locks – the full mechanical digital category
- Changing Codes on Mechanical Digital Locks
- MG Pro & ECP Explained
- Passage Mode vs Holdback Mode
- Why Double-Sided Locks Are a Smart Choice
- Lockwood vs Borg vs Carbine
- Heavy Duty Commercial Mechanical Digital Locks
- Buyer's Guide Ch 16 – Mechanical Digital Locks
What's In The Box - Borg BL2620MGBC
- Borg BL2620MGBC outside knob keypad assembly (polished chrome)
- Borg BL2620MGBC inside knob keypad assembly (polished chrome)
- 60mm anti-thrust stainless steel tubular latch
- Strike plate and box keep
- Spindles (to suit door thickness 35–80mm)
- M4 fixing screws
- 2 × coded tumblers (red – spare)
- 2 × non-coded tumblers (blue – spare)
- Tweezers (for tumbler code change)
- Hex wrench (Allen key)
- Handle screw rubber grommet × 2
Borg BL2620MGBC - Dimensions
PDF Files - BL2620MGBC
Step-by-step tumbler code-changing procedure – remove the cover plate, reposition red and blue tumblers with the supplied tweezers.
Tubular latch installation guide for the BL2600 series – strike plate, drilling, spindle, and keypad/handle fitting.
Fold-along drilling template plus the parts list and tumbler code-change procedure this page's combinations figure is sourced from.
General maintenance guide for Borg mechanical pushbutton keypad locks.
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
- 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.
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.
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