Pushbutton Lock 2900-DC is mechanical keyless double sided combination, narrow stile deadbolt lock with Satin Chrome finish. The 2900 Series locks are meant to be mortised into the door frame. Replaces Adams-Rite style lock. It is dedicated to narrow stile doors and cabinets. On exterior is installed knob. One user code with thousands of possible combinations works as a lock key. Lock is bump proof, pick proof, and hacksaw proof to provide heavy duty security for gates or doors. The mechanical pushbutton lock requires no wires, batteries or electricity. Locks fit doors 1 3/8" to 2" thick with a 1 1/8" backset. The Pushbutton Lock is very easy and quick to install - installs in minutes with EZ plates and very easy to change code. For thicker doors, an Extension Kit is available - extensions for doors up to 5? in width. The 2900-DC is changeable handing.