TSS Retro Fit British Standard 5-Lever Mortice Deadlock | BS3621 High-Security Door Lock | 40 mm Backset Mortice Deadlock | 5-Lever Dead Lock for External Doors | with Fixings (Brass, 3 Inch)

Check Measurements Before Ordering Ensure compatibility by comparing all measurements with your existing Mortise Lock before purchase. Full measurements in images.
British Standard / High Security Certified to BS3621 for insurance-approved security. High-strength 5-lever mechanism with anti-drill and anti-saw protection helps resist forced entry and enhances door security.
Retro-Fit Replacement – 40 mm Backset (for 2.5") 53mm Backset (for 3") Designed with the same dimensions as classic UK mortice deadlocks, including a 40 mm backset. Ideal for upgrading old or worn locks without altering the door.
Supplied with Fixings & Accessories Includes 2 keys, matching faceplate, strike/keep plate, screws and escutcheons — everything required for a complete installation with no extra parts needed.
Durable Traditional 5-Lever Mechanism Reliable lever system (not detainer) provides smooth, consistent locking performance and long-term durability for external timber doors.
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