@jacqueslees: Eccentric Bolt Bolt — A mechanical component: a cylindrical threaded fastener used in conjunction with a nut. A bolt is a type of fastener consisting of two parts: the head and the shank (a cylinder with external threads). It must be used together with a nut to fasten and join two parts that have through-holes. This type of connection is called a bolted connection. Since the two parts can be separated by unscrewing the nut from the bolt, the bolted connection is classified as a detachable (non-permanent) connection.