The Union 2134E 80mm Keyed Alike 5 Lever BS3621 Insurance Rated Deadlock Satin Chrome is most commonly used to add extra security to external doors with a night latch or rim lock & has been tested to British Standard 3621:2004. The deadbolt is locked or unlocked by a key either side. It has a quality steel case (red enamelled) & solid brass deadbolt, finished with satin chrome finish. Other Variations The lock is also available as a keyed to differ lock, with an 67mm case size (45mm backset) & with a polished brass finish. Some of these variations can be found in the relat...