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 5920-01-039-5393
NSN 6135-00-134-6648
NSN 6220-00-712-1779
NSN 5990-01-485-0260
NSN 6650-00-762-0267
NSN 6650-00-758-7485
NSN 6145-01-222-3172
NSN 6620-01-426-2220
NSN 6145-01-544-1391
NSN 5965-01-550-3711
NSN 7035-01-219-7987
NSN 6650-00-424-7239