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 6685-01-012-2854
NSN 6610-00-064-5514
NSN 6105-01-441-0048
NSN 5910-00-339-7591
NSN 6145-01-507-8147
NSN 5996-00-257-5646
NSN 5999-01-122-7903
NSN 6685-01-492-4491
NSN 5935-00-665-4421
NSN 5935-00-106-8264
NSN 5945-01-306-6205
NSN 6650-01-321-1684