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 7035-01-145-5059
NSN 5905-00-666-4983
NSN 5935-00-409-5625
NSN 5975-00-176-4651
NSN 5990-01-116-2181
NSN 4140-00-787-1315
NSN 5855-01-343-7943
NSN 6145-00-164-0723
NSN 6145-01-414-4207
NSN 5920-01-206-9947
NSN 6610-01-412-5776
NSN 5960-01-111-3372