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 6150-01-032-4556
NSN 6650-01-391-4461
NSN 4140-00-332-5956
NSN 5996-01-026-9981
NSN 6610-01-465-1320
NSN 6320-00-456-0836
NSN 6610-01-147-7221
NSN 6110-01-165-0499
NSN 6135-01-010-0891
NSN 6645-00-385-3684
NSN 6105-00-074-3223
NSN 5975-01-541-4972