General description The Yale 77 Series Traditional Nightlatch is a classic and reliable lock designed for exterior doors. It features a hardened brass case finished in Brasslux and includes a polished brass cylinder. The nightlatch is operated with a key from outside and a knob handle from inside, providing secure locking. It has a deadlocking snib function that allows the latch to be held back or deadlocked internally. Suitable for doors with a 60mm backset, it is ideal for traditional-style doors and is supplied with two keys. Technical specifications Finish: Brasslux Material: Hardened brass case Backset: 60mm Supplied with: 2 keys and external cylinder (model 1109) Security rating: Standard Compatibility and accessories Compatible with doors requiring a 60mm backset Supplied with external cylinder (model 1109) Not recommended for glass panelled doors unless used with a 5-lever mortice lock Installation Designed for surface mounting on external doors Requires a 60mm backset