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 5835-00-251-9138
NSN 5950-01-344-5035
NSN 5990-01-290-1425
NSN 6620-01-446-7290
NSN 5935-01-215-0589
NSN 5990-00-707-0731
NSN 7035-00-421-8710
NSN 5920-00-172-9232
NSN 5990-01-548-3711
NSN 5999-00-399-7866
NSN 5996-00-254-6355
NSN 6105-00-142-5901