A headless fastener externally threaded on both ends with each threaded portion of one but not necessarily the same nominal diameter. It is designed to be locked in place by either a ring, lock, serrated or a ring, lock, keyed.
NSN 6130-01-527-1892
NSN 6650-01-049-5361
NSN 5999-01-388-9398
NSN 6610-01-641-4191
NSN 5990-01-462-1617
NSN 5910-01-559-9149
NSN 5998-01-634-0604
NSN 6145-01-212-4777
NSN 6105-01-266-6866
NSN 4140-00-337-6631
NSN 6220-00-272-7497
NSN 5996-00-379-8785