Glossary of Terminology

Stuck on a term? We're here to help! Learn the terms used for different locks and components and find out what they do in this useful glossary covering our most commonly used jargon. 



Anti-shim Plunger

Also Known As: Deadlocking Plunger

Prevents unlawful shimming of the latch.

Audible Keypad

A keypad which 'beeps' when a button is pressed.

Audit Trail

A list of entries and/or events which have occurred on the lock. 

Auto Lock/Unlock

Automatic latch engagement either unlocking or locking after a set period of time, or at a specific time. 


Back Plate

Also Known As: Backplate

The mounting plate which is attached to the door to allow a latch to be attached to.

Back to Back

Also Known As: Two Coded Plates

Front plate with keypad on both side of the lock providing coded access in both directions.


A measurement taken from the door edge to the centre of the spindle hole.

Battery Override

The ability to override the battery if it is completely flat and gain access to the lock. On selected KitLock by Codelocks locker locks a PP3 battery can be placed over the external contacts to gain function when power has been lost.


The part of a lock which protrudes from the lock case into the frame keep or strike plate.

BS 3621

The standard specification for door locks. To be awarded this standard a lock must have the ability to be dead locked and the key taken away from both sides so no one can gain access or exit the door without a key.


C3 Smart App

A smartphone App compatible with Codelocks Smart Locks offering programming and client creation over Bluetooth. Easily view, access and edit locks from one screen. Unlock locks with just one tap, or swipe to amend settings and view audit history logs.

Cabinet Lock

A term for all locks use on furniture such as cupboards, drawers, filing cabinets etc.


A simple locking mechanism composing of a rotating arm which catches on the door frame when locked.

Card Client

Also Known As: Smart Card

A 13.56MHz RFID MIFARE card which can be used to gain entry to compatible locks.

Classroom Function

Ability to set the lock into ‘Code Free’ mode using the key. This is done by installing the optional cylinder tailpiece included in the box.

Code Client

Also Known As: User Code

A numerical code created for access, varying on the lock model this can range from four to six digits. 

Code Free Access

Also Known As: Hold Open

A feature in which supported locks do not require a code for a user to gain access.

Coded Alike

Coding a lock to match an existing code. 


The part of the lock where the key is inserted into and turned to unlock.



A lock bolt that is moved by turning a knob or key without the action of a spring.


Also Known As: Nightlatch

A sprung loaded self-locking latch where the bolt is by default engaged and retracted when either a key or correct code is used.


An extra part on the latch which prevents breaking in by forcing a credit card etc.

Door Face

The surface of either side of the door you are fitting a lock to.

Door Frame

The inner or outer door surrounds e.g. a strike plate is fitted into the door frame.

Double Euro Profile Cylinder

Also Known As: Passage Free Access/Hold open

A type of lock cylinder that allows key access from both sides of the door, predominantly used in Europe.

Dual Backplate

A backplate with a switch which, if used, puts the lock into the Hold Open/Passage Free Function.

Dual Code Mode

A mode of entry where two different authorised codes must be used to gain access.


Easy to Fit

All of our locks come with full installation instructions, and necessary parts ensuring they are easy to fit.



To be used in conjunction with a Mortice latch, bringing the lock up to the 30 or 60 minute fire door BS EN 1634-1:2008 standard.


A hole in the lock or latch mechanism in which the spindle fits through and is used to engage the lock or latch.

Front Plate

Also Known As: Faceplate

The lock face with keypad, used for programming and gaining entry. Also available in pairs to allow coded access in both directions. See 'Back to Back'.



Also Known As: Getting Started Guide

A basic guide outlining how to set up the lock and its features. More information can be found in the full programming and operating instructions.


Hold Open Function

Also Known As: Passage Function

The lock can be set to remain in an unlocked state until told otherwise with a pre defined code.



Also Known As: Inner Box

Abbreviation for “Inner Box” artwork.


Also Known As: Installation Instructions

Instructions on how to install the lock on a door or cabinet. 


Also Known As: Installation Template

A guide which if printed, can be used as a template for drilling the holes needed for installation. 


K3 Connect App

A smartphone App compatible with Codelocks Smart Locks offering programming and client creation over Bluetooth. This App is no longer available and was replaced by the C3 Smart App on 14th February 2023.

Key Cutting

When a key is cut to match an existing key.

Key Override

The ability to unlock using a physical key rather than entering a code. 

Keyed Alike

An additional key cut to match the new lock's key.



Also Known As: Spring Loaded Latchbolt

A spring-loaded locking bolt moved by turning a knob or key.

Lock Case

This is the unit which keeps the door closed and contains several parts (i.e. a deadbolt, bolt, latch) which vary based on the chosen lock.  


Marine Grade

A coating resistant to moisture and salt spray following rigorous salt spray testing for up to 1000 hours.

Master Code/Card

The owner of the lock(s) will usually be in possession of the Master Code/Card. This is a management tool which can be used to control all other codes/cards, programming and administration related to the lock(s).

Master Key

A physical key which will open the lock.


The leading brand of contactless integrated circuit products. MIFARE™ chips are used in our smart cards.

Mortice Deadbolt

A lock housed within the door containing a bolt, but no latch, which protrudes into the door frame's strike plate holding it closed until retracted.

Mortice Latch

A latch housed within the door which catches the strike plate on the door frame.

Mortice Lock

A lock fitted within the door, housing the mechanism protruding from the door's edge which catches the strike plate on the door frame.  These are also available as a latch, deadlock or sashlock.


Neoprene Seals

Also Known As: Rubber Gasket

Seal made from Neoprene rubber which prevents water ingress in the front and back plates.


An algorithm generated six or seven digit, time-sensitive code that can be sent to lock users remotely to allow temporary access.

Non Handed

Locks which are 'non-handed' can be hung on the left or the right side of doors. 



Also Known As: Outer Box

Abbreviation for “Outer Box” artwork.


Patch Fitting

Surface mounted latch mechanism used with Glass Doors

Phone Client

Also Known As: Phone User

A C3 Smart App user who can unlock Smart Locks with App on their mobile device. 


Also Known As: Programming and Operating Instructions

The full instructions and list of programming sequences for a lock. 

Private Use Function

This function is used where the same code will be repeatedly used, e.g. an employee with the same locker/drawer in the workplace.

Public Use Function

The same code is entered once only to open the lock before automatically being erased and ready for the next user. This function is used for short term, multiple occupancy applications, e.g. hot desking in an office or a locker in a sports club.



The QuickCode Function is an option that allows the code to be changed while the lock is fitted to the door. This is a convenient option in which code holders can quickly change codes.


Rebate Kit

A conversion kit comprising a strike plate and face plate used for rebated doors allowing the latch to be fitted flush.


Fitting a new lock to an existing installation. 


Also Known As: Radio-frequency Identification

A contactless means of near field communication used to transmit data between a chip and transmitter, usually a smart card and lock.


Also Known As:  Real Time Clock Setting

The lock’s clock which runs adjacently to the actual time set during programming.



This lock contains a latch and deadbolt which need to both be engaged to open and close the door. 

Slam Latch

A KitLock accessory that allows ‘push shut’ locking of the door without needing to turn the handle.

Smart Card

Also Known As: Card Client

A feature in which supported locks do not require a code for a user to gain access.

Smart Lock

Locks that can be managed remotely via the C3 Smart App, and accessed via code, card or phone.


A long square rod passing from one handle through the door via the lock to the other handle or knob which operates the latch.

Strike Plate

Also Known As: Keep

A metal plate fixed into the frame of the doorway, aligned with the lockset in order to give the latch a place to sink into when the door closes.

Sub-Master Code/Card

A secondary eight digit Master Code/Card that does not retain the whole range of programming/administration capabilities.

Surface Deadbolt

A bolt protruding from the lock's back plate used for locking instead of the traditional mortice latch which requires drilling the door.


Technician Code/Card

This six digit code when used will retain the already pre-defined user codes e.g. used when a cleaner/caretaker requires access.


Tumblers are pins used to set the code on mechanical locks (excluding QuickCode compatible locks).


User Code/Card

Also Known As: Code/Card Client

A standard four digit access code/card assigned to everyday users which can only perform the basic locking and unlocking of the lock.




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