The mandible is further advanced when the body wire is moved through the head-gear tube cylinder. . Sliding the wire towards the posterior opening a space the thickness of a dime between the back of the head-gear tube and the lock will advance the mandible another millimeter.

Gently unlock the hex-head screw to release the hold of the lock on the wire and slide the lock body to close the space you created. Gently, with finger pressure, lock down the hex-head screw.