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 6645-01-534-5545
NSN 5935-01-216-4721
NSN 6130-00-503-7865
NSN 5945-01-232-9939
NSN 6145-01-444-4509
NSN 6320-01-352-5653
NSN 5985-01-446-0371
NSN 5855-01-497-0467
NSN 5910-01-251-8156
NSN 5998-01-122-9007
NSN 6620-01-259-5944
NSN 5990-00-945-1033