General description This Yale P85 Deadlocking Nightlatch is designed for secure locking of external doors. It features a hardened case finish in Dark Metallic Grey and a satin chrome cylinder. The lock is key operated from the outside and lever handle operated from the inside, making it ideal for properties left unattended for long periods. The latch automatically deadlocks when the door is closed, and the snib function allows the latch to be held back. Additionally, the inside handle can be deadlocked by a reverse turn of the key, providing extra security. Technical specifications Backset: 40mm (distance from door edge to center of keyhole) Suitable for door thickness: up to 57mm Durable five-pin cylinder tested for corrosion resistance Tested for at least 100,000 cycles of use Available finishes: Brasslux, Chrome, Dark Metallic Grey Compatibility and accessories Supplied with 1109 cylinder Includes internal nightlatch, strike plate, and external cylinder Additional keys can be