These expanding pin 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 of over tightening by the operator. These fasteners only require a tapped hole in the plate or panel to be mounted and a through hole in the base plate. They are designed to be used without receptacles. Pressing the button allows the pin to be inserted into the hole. Releasing the button expands the shaft to hold the fastener firmly in place. They body and nut are made from 303 stainless steel. The spacer is made from 303 stainless steel. The spring and snap ring are made from 304 stainless steel.