Only hinge mandibular movements are possible. In this position the mounting of the casts is carried out as well as the control of occlusion in centric.
Locks fully up
In this position protrusive and back to centric, Bennett, balancing and all intermediary movements can be carried out as in the natural TMJ.
Locks fully forward
With the locks in this position a full envelope of natural mandibular movements is possible including the control of the retrusive movement. (Position for grinding-in of prostheses according to the functional chewing movements).