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 6130-01-634-0603
NSN 5965-01-187-4008
NSN 6135-01-122-2656
NSN 5915-01-440-3998
NSN 5920-00-008-4770
NSN 5855-00-310-2740
NSN 6685-01-337-3504
NSN 5835-01-161-7461
NSN 5945-01-194-7542
NSN 6610-01-250-2811
NSN 6620-01-247-4127
NSN 5998-01-306-6454