Lockwood Selector® 3787 Short Backset Dual Entry Mortice Locks

3787 Dual Entry Mortice Lock 23mm Backset - Stainless Steel
3787 Dual Entry Mortice Lock 23mm Backset - Stainless Steel
4787 Dual Entry Mortice Lock 25.4mm Backset - Stainless Steel
5787 Dual Entry Mortice Lock 30mm Backset - Stainless Steel
6787 Dual Entry Mortice Lock 38mm Backset - Stainless Steel

A comprehensive range of cylinder mortice locks for narrow stile hinged doors. Suitable for heavy duty use in industrial and commercial buildings, institutions, clubs, schools, hospitals, hotels and similar buildings.

Designed to enable third parties such as emergency services to enter specific areas by second cylinder; without giving access to all locksets in the building and the ability to lockout keys with restricted access at certain times.

Features and Benefits

  • Easy red/green function setting
  • All lock settings are made from under the faceplate allowing for simple in-door configuration
  • Standard primary locks include anti-lockout and holdback capabilities
  • Improved cylinder functions including lock/unlock and retract latch as standard
  • Reduced range of cylinder cams and turn adaptors relative to other commonly available commercial cylinder mortice locks


Compatible with Lockwood 4800 and 5800 Series Furniture

Lockwood Plate Door Handles – More information

Case and Faceplates

  • High purity zinc alloy material cases with stainless steel chassis plates. Stainless steel faceplates provided as standard
  • Brass faceplates available for alternative finishes


  • 23mm standard backset
  • Extended backsets 25.4mm, 30mm and 38mm are available

Latch Bolts

  • Latch bolts are made with stainless steel, 15mm in size
  • Deadlatching is achieved by an auxiliary stainless steel latch bolt
  • Reversible for both left and right hand doors, opening in or opening out whilst lock is in door
  • Electric Strike compatibility
  • Separate auxiliary bolt moves into lock case simultaneously with latch bolt
  • Radius bolt provides greater deadlatch throw and smoother closing action

Cylinder Retaining Pin

Hard-drawn spring steel wire, corrosion protected.

Door Thickness

  • Metal doors: 43 to 46mm
  • Suits hollow-style aluminium door sections with 38mm minimum internal depth

Door Clearance

To ensure correct functioning of the deadlatching mechanism and security for all locks, the clearance between the door and the frame should be 3mm. The deadlatching will operate up to 8mm door clearance, however door clearances over 5mm are not recommended.


All Selector® 3780 Series Cylinder Mortice Locks conform with Level S7 (Physical Security) Australian Lock Standard (AS-4145.2-2008). Conforms to Level S8 (Physical Security) when fitted with door furniture and anti-drill cylinder.


All Selector® 3780 Series Cylinder Mortice Locks conform with Level D8 (Durability) Australian Lock Standard (AS4145.2-2008).


All Selector® 3780 Series Cylinder Mortice Locks conform with Level C6 (168 hours) Australian Standard (AS4145.2-2008).


Requires standard Lockwood oval shaped brass cylinders and brass barrels. Lockwood cylinders include bump resistant five pin tumbler mechanism.

Functions require the use of different cams and adaptors.

Lower cylinder is a 570E type cylinder which must be ordered separately

Restricted Special Keying

Lockwood locks can be keyed to a number of controlled and/or specially keyed systems. These range from legally protected keys to protect against unauthorised duplication and can also include specially designed keying systems such as master key systems. This allows for different levels of mechanical access control.

Lockwood Keying Platforms – More information

Standard Finishes

Stainless Steel SS

Extended Cylinders

Modular Cylinder Extensions are available for thicker doors.


Rebate kits to suit 13mm standard rebate are available. Only suitable for use with 30mm and 38mm backset locks.

Electric Strikes

Lockwood offers a wide range of electric strikes which are compatible with the Selector® 3780 Series Mortice Lock.

Lockwood Electric Strikes – More information



Part Number 3787 4787 5787 6787
Dimension X 23 25.4 30 38
Dimension Y 40 42.4 47 55
Minimum Internal Depth of Door 40 43 47 55




Part Numbers

Lockwood Selector 3787 Short Backset Dual Entry Mortice Locks


Primary Locks

Description Part Number
3782 Universal Primary Lock 23mm Backset 3782SS
4782 Universal Primary Lock 25.4mm Backset 4782SS
5782 Universal Primary Lock 30mm Backset 5782SS
6782 Universal Primary Lock 38mm Backset 6782SS


Conversion Kits

Description Part Number
Dual Entry Kit To Suit 570E Type Cylinder 3787-KIT570E

Australian Made

Designed and built in Australia according to high quality standards.

Where to buy?

Find your local Lockwood stockist.

Disclaimer: Selector is a registered trademark of ASSA ABLOY Australia Pty Ltd in New Zealand