General description The Yale P77 Traditional Nightlatch is a classic and reliable door lock trusted by millions for over 70 years. It features a traditional design with a key-operated external mechanism and an internal knob handle for easy operation from inside. The nightlatch includes a deadlocking snib to hold back or deadlock the latch internally, providing added security. Suitable for inward opening doors up to 57mm thick, it is ideal for residential use and offers a straightforward, secure locking solution. Technical specifications Backset: 60mm (distance from door edge to center of keyhole) Finish: Polished Chrome Security Rating: Standard Supplied with: 2 keys and fixing pack Compatibility and accessories Compatible with Yale rim cylinders Supplied with external cylinder Not recommended for glass panelled doors unless used with a 5-lever mortice lock Installation Designed for inward opening doors up to 57mm thick Requires standard fixing and fitting procedures for nightlatches