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. ANSI/BHMA grade 2 certified. Locking mechanism functions by pressing the push button on the interior of the lock. Fully reversible lever can be installed on both right handed and left handed doors. Easily installs in minutes with just a screwdriver. Comes with 2 keys.