The Yale Deadlocking Nightlatch offers high security for your door. It features an internal lockable handle and automatic deadlocking for enhanced protection. The anti-bump design provides greater security and peace of mind. This nightlatch includes a snib button that allows you to deadlock or hold back the latch from the inside, making the lock inoperable by key or handle when snibbed. It is supplied with a Yale 1109 5 pin cylinder and two keys. The inside handle can be deadlocked by a reverse turn of the key in the outside cylinder after closing the door. This narrow design variant has a 40mm backset and comes in a silver finish. It is a reliable and secure option from one of the world's most trusted brands. The latch automatically deadlocks upon closing the door. Backed by a two year manufacturers mechanical guarantee.