Standard brass mortise lock with a standard 2 1/4" back set. This mortise lock is available in 3 different finishes. The lock box measures 4" tall, 3" in depth and 1/2" thickness. The distance from the center of the knob hub to the center of the round part of the keyhole is a standard 2 1/4". The lock face plate measures 6" tall by 7/8" wide and the strike plate measures 5 1/8" tall by 1" wide. Both the lock face plate and strike plate are solid brass.