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 6650-00-641-6139
NSN 5925-01-438-8542
NSN 6130-01-325-9904
NSN 6110-00-082-0268
NSN 5935-01-169-1709
NSN 5935-01-512-4809
NSN 5920-00-577-4716
NSN 6135-00-833-9909
NSN 7035-00-205-1932
NSN 5950-01-178-0269
NSN 5985-01-545-3638
NSN 5975-00-971-8863