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 5925-01-415-3084
NSN 5975-01-634-0678
NSN 4140-01-613-6427
NSN 6240-00-145-8167
NSN 5910-01-633-9963
NSN 6110-01-307-8899
NSN 6645-01-333-9336
NSN 6220-01-400-4203
NSN 5925-01-265-7749
NSN 6650-01-499-3750
NSN 6220-01-622-5496
NSN 6685-01-338-6131