Yale 85 Deadlocking Nightlatch - Grey - 40mm BacksetYALE 85 B 85 DMG PB 40 DEADLOCKING NIGHTLATCH DMG 40MM BACKSET, BRASS CYLINDER FINISH (DARK GREY) The Yale P85 (40mm) & P89 (60mm) are deadlocking nightlatches suitable for left & right handed, and inward opening doors with a thickness of up to 57mm. The Yale 85 deadlocking standard nightlatch high security locks are widely used front door latches. It key operated from the outside and lever handle operated from the inside. The latch automatically