Kwikset 91580-004 Round Single Cylinder Deadbolt featuring SmartKey in Polished Chrome Designer style and superior security with this Kwikset Signature Series product For use on exterior doors where keyed entry and security is needed Featuring SmartKey re-key technology; re-key the lock yourself in seconds in 3 easy steps Deadbolt operated by key outside and thumb turn inside Features an adjustable latch to fit all standard door preparations