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 6610-01-211-8956
NSN 5945-01-502-7852
NSN 5990-00-163-4173
NSN 5960-00-715-9227
NSN 6610-00-905-6780
NSN 5930-00-235-9455
NSN 5990-01-352-5255
NSN 5855-01-361-2362
NSN 2925-00-478-3742
NSN 5945-00-276-3189
NSN 6220-00-017-9136
NSN 2925-01-565-6410