DPH-400W (4-inch dia.) diaphragm chucks with special jaws and stops. The stops have (3) small "Air Detect" holes for part seating conformation. Air is pumped through these holes, and when the part rests on the stop, the air pressure rises, tripping a pressure switch that tells the machine to start machining. The (4) clover adapters have grooves for a CAM follower to snap into in order to orient the chuck when stopped. Up top is an (8) passage rotary union to actuate all four chucks independently. Please call for further explanation. These are mounted to a (4) spindle Theilenhaus machine.