@jacqueslees: Elevator Bolt (Lift Bolt) / Bolt A bolt is a mechanical component—a cylindrical, externally threaded fastener used together with a nut. A bolt consists of two parts: a head and a shank (a cylinder with external threads). It must be used in conjunction with a nut to fasten two parts having through-holes. This form of connection is called a bolted connection. Since the two parts can be separated again by unscrewing the nut from the bolt, a bolted connection is a detachable (removable) connection.