The Kaba Mas CDX-10 consists of an X-10 high security lock, Federal Specification FF-L-2740B , mounted on a deadbolt base plate. The base plate is surface-mounted to the inside face of the door. The deadbolt base plate has two essential features.
First, it provides a means of latching the bolt in the retracted position. This prevents the bolt from being inadvertently extended.
Second, turning the knob on the base plate will retract the bolt to allow egress.