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 6685-01-425-3128
NSN 5998-00-978-4474
NSN 6220-01-466-6847
NSN 6610-01-095-1459
NSN 6110-01-142-2550
NSN 7035-01-008-7248
NSN 5920-01-605-2457
NSN 5950-01-450-2280
NSN 6620-01-218-8048
NSN 6645-01-113-2525
NSN 5996-01-313-2644
NSN 6650-01-282-8015