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 5999-01-417-3028
NSN 6685-01-182-3634
NSN 5895-01-033-1419
NSN 5925-01-054-5473
NSN 5990-01-561-7802
NSN 5855-01-434-7520
NSN 6150-01-062-0853
NSN 6135-01-613-1464
NSN 6650-01-258-0811
NSN 6105-01-435-5530
NSN 4140-01-619-0289
NSN 7035-01-013-0934