Kartrite Push Button Digital Combination Security Door LockKartrite Push Button Digital Combination Security Door Lock Secure your home, business and items without the need for keys and the associated issues they present like key management, loss of keys, and difficulty of change. So losing or forgetting a key is no longer an issue with the keypad lock. The benefit of outfitting your door with a mechanical push button lock is that you never have to worry about replacing the batteries! Mechanical door locks