About this item Unlock your door without keys by entering your code on the lock’s backlit keypad; Lock the door behind you by pressing any button or by enabling Auto Relock. Never hid a key again, create unique entry codes for the people you trust. Delete codes anytime you need to. Don’t worry about getting locked out due to dead batteries – the lock has a back-up charger so you can give the lock power with a 9V battery to enter your code The lock is 100% key free meaning it’s amper proof and there’s no keys to lose or copy. Replaces your existing deadbolt in minutes on standard doors, 1-3/4″ to 2-1/4″ thick with just a screwdriver. Features a BHMA Grade 2 certified deadbolt that’s fully motorized and very quiet. Backed by Yale, the world’s favorite lock brand since 1840 with a lifetime limited warranty on finish and mechanical hardware.