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 6135-00-801-0587
NSN 5855-00-791-5000
NSN 5920-01-250-1299
NSN 5975-01-178-0938
NSN 5915-01-468-7714
NSN 5945-01-659-1863
NSN 6150-00-057-4099
NSN 5990-00-242-3754
NSN 6105-01-115-1050
NSN 5998-01-477-6173
NSN 6110-00-510-3788
NSN 6645-01-582-2601