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 6130-00-725-1764
NSN 6650-01-120-6231
NSN 6145-00-876-4449
NSN 6150-00-528-4175
NSN 6650-00-229-3790
NSN 5985-00-153-0864
NSN 6130-00-304-4827
NSN 5910-01-646-1035
NSN 6320-01-096-6649
NSN 6645-00-124-9939
NSN 6240-00-233-3481
NSN 6685-00-941-0534