This single cylinder deadbolt can be locked or unlocked by a key on the outside, or the turn piece on the inside. 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. Features an adjustable latch to fit all standard door preparations. Locking mechanism functions with turn piece on the interior of the lock. 1 in. deadbolt throw. ANSI/BHMA grade 2 certified. Comes with 2 keys. Easily installs in minutes with just a screwdriver. Lifetime mechanical and finish warranty.