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 6620-00-199-8734
NSN 5985-00-822-2382
NSN 5960-00-147-0519
NSN 5998-01-255-6886
NSN 6610-00-958-0294
NSN 6110-00-097-0617
NSN 5965-00-791-0964
NSN 6130-00-400-5774
NSN 6685-01-656-1282
NSN 6135-01-041-3829
NSN 6620-01-214-7520
NSN 5930-00-434-9824