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 5935-00-486-0930
NSN 5975-01-045-3705
NSN 6220-00-587-1818
NSN 6320-01-512-2031
NSN 5925-00-666-4753
NSN 5855-00-560-0110
NSN 5999-00-990-7334
NSN 6240-00-435-0433
NSN 6685-01-644-8385
NSN 6135-00-078-9931
NSN 5945-00-221-6529
NSN 6240-00-144-4693