To provide secure locking of prison cell doors, with facility for 'Privacy' locking under control of inmate.


The 4L65P can be either surface or flush mounted and is of robust construction based on the Chubb Lock Custodial Services standard cell lock footprint. The main bolt is an un-sprung rectangular deadbolt providing of throw of 32mm.

Staff Key. Locking/unlocking is achieved by a full turn of the key allowing the handle to throw or withdraw the bolt. When the key is withdrawn the main bolt can be left in two positions fully thrown (i.e secure when door in frame) or bolt fully withdrawn and locked back.
Withdrawal of the main bolt will automatically withdraw the prisoner’s ‘privacy’ bolt if thrown.
Privacy Key. The ‘Privacy’ bolt can be locked/unlocked from outside by a pin tumbler cylinder or from inside by a cylindrical knob.
Note: Locks can be prepared to accept customer’s choice of cylinder, details of which need to be supplied prior to ordering.


Solid Case Technology; Lock case machined from single piece carbon steel.
Steel main bolt, with carbide anti-cutting rollers and 32mm throw.
External visual locking status indication.
Independent 7-lever locking mechanism.
Factory restricted key sections.
5 bolt secure fixing.
Integral baffle arrangements to resist interference via the keyhole.
Privacy facility using secondary mechanism.
Internal knob with clutch mechanism to ensure staff always have control of lock
Escutcheon designed to give positive key alignment.


Mechanical locking mechanism tested to a minimum of 100,000 operations.
Handle mechanism tested to a minimum of 100,000 bolt operations. 

Additional features

Range of furniture options available.
Range of fixings including backplates, stud fixings, locking plate and keeps.
External handle designed to shear under excessive load to prevent damage to
internal lock mechanism.
Interchangeable mechanical inner locking unit to enable re-coding.
Can be configured to differ, to pass or under a master key scheme.

Materials and finishes

Lock case - carbon steel electro-plated and powder coated exterior.
Main bolt - carbon steel electro-plated.
Main bolt follower - high tensile brass.
Keys – Hardened Steel. 
Levers and springs – Brass / phosphor Bronze.
Inside knob Stainless Steel.

Dimensions and Weights

Case Height 286mm
Case Length 267mm
Case Thickness 29mm
Bolt Throw 25mm
Bolt Depth 45mm
Bolt Thickness 22mm 

Weight (lock only) 12.4Kg

Total Range

The lock is available in left or right hand variants for opening in or opening out doors and can be fitted
to steel or wooden doors. A range of backplate stud lengths is available to suit door thicknesses from 25 to 70mm.

Fully dimensioned customer drawings are available on request to assist with door preparation.