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 6220-01-253-8827
NSN 6645-00-833-2395
NSN 5905-01-003-9660
NSN 6110-01-029-6805
NSN 5999-00-530-4844
NSN 6220-01-476-8889
NSN 6110-00-054-7278
NSN 6150-01-059-4304
NSN 5945-01-509-4685
NSN 5999-01-154-1058
NSN 5998-01-476-7352
NSN 6240-01-562-4891