A metallic headed fastener having internal threads for a portion of the full length. it may have a smooth, hexagon or splined shank with an open or closed end. it is designed to be expanded tightly against the material it is being installed in by means of a special tool. the item must have a specified grip range. the grip range is the thickness of the material the item is being installed in. an integral feature is incorporated for locking on the threads of a mating member.