The Yale Deadlocking Nightlatch offers high security for your door. It features an internal lockable handle and automatic deadlocking upon closing the door. Enhanced with anti-bump technology, this nightlatch provides reliable security. It is supplied with a Yale 1109 cylinder and two keys. This specific variant features a narrow 40mm backset. The snib button allows you to deadlock or hold back the latch internally, making the lock inoperable by key or handle when engaged. For additional security, the inside handle can be deadlocked by a reverse turn of the key in the outside cylinder after closing the door. This widely used front door latch from Yale is key operated from the outside and lever operated from the inside. It comes with a two year manufacturers mechanical guarantee.