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 5910-00-817-5227
NSN 6135-01-119-0720
NSN 6145-00-575-7190
NSN 5996-00-186-8709
NSN 5965-01-095-1352
NSN 5945-01-255-7968
NSN 5998-01-040-3980
NSN 5835-00-617-3578
NSN 6220-00-030-6728
NSN 5999-01-191-9045
NSN 6620-00-538-8746
NSN 5998-01-371-0848