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 5920-00-432-1515
NSN 6240-01-351-3747
NSN 2925-01-097-0903
NSN 5930-00-519-0662
NSN 5915-01-596-6467
NSN 4140-00-854-8871
NSN 6135-00-134-6648
NSN 5975-01-172-5965
NSN 5960-00-017-2892
NSN 5975-01-586-6978
NSN 5935-01-563-8737
NSN 5999-01-158-8887