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 2925-00-588-5592
NSN 6150-01-264-5550
NSN 6240-01-381-2275
NSN 6685-00-001-6459
NSN 5975-00-988-3493
NSN 5855-01-319-9757
NSN 5935-01-608-1946
NSN 6150-00-679-3285
NSN 6240-01-100-2597
NSN 6145-00-835-1088
NSN 4140-01-647-0097
NSN 5920-01-642-1570