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 4140-01-214-8577
NSN 5985-01-468-5598
NSN 5910-00-496-7629
NSN 5925-00-316-5312
NSN 5990-00-179-2576
NSN 5965-00-518-0958
NSN 5915-01-488-9469
NSN 5990-01-210-5474
NSN 5935-00-839-1431
NSN 7035-01-623-9555
NSN 5835-01-218-5560
NSN 5855-01-125-9167