These retractable fasteners provide positive locking in quick change applications where there is frequent insertion and removal of a fixture. They allow for consistent fastening force eliminating the chance for under or over tightening by the operator. They are designed to be used with the cam receptacle referenced in table. The fastener is mounted to the fixture and the receptacle is mounted to the base. The spring in the fastener allow for a range of fixture thicknesses. Turning the knob one quarter turn aligns and locks the fastener into place. The fasteners are marked with "ON" and "OFF" indicators to show the position of the fastening pins. Three socket head cap screws for mounting are included (M3X0.5 - 6 mm long or M2X0.4 - 5 mm long). The bodies are made from 303 stainless steel. The shank is made from SKS3 steel with an electroless nickel plated finish. The pins are made from 420J2 stainless steel. The knob is made from black plastic.