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 5950-00-760-8194
NSN 5910-01-570-2178
NSN 5998-01-237-2541
NSN 6150-01-558-3078
NSN 5935-01-497-0731
NSN 6620-00-675-6689
NSN 6620-00-100-4517
NSN 6145-01-284-0017
NSN 5920-01-219-0724
NSN 5925-01-050-8195
NSN 4140-01-286-3682
NSN 5996-00-719-6225