Narrow ERA BS Night latch - Available in brass or chrome (40mm backset). Features an integral cylinder pull which protects the cylinder from being drilled and has over 30,000 cut key variations. 20mm bolt throw for greater security and strength. Ideally suited for glass panelled wooden doors. The main lock bolt “automatically” deadlocks, this makes the use of a credit card to force entry virtually impossible.The bolt can also be held in the withdrawn position (only) with the use of the snib feature. The BS High Security Nightlatch conforms to British Standard 3621:2004 (BS EN 12209).