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 6240-01-531-1684
NSN 5960-00-274-4905
NSN 6645-01-086-7668
NSN 5985-01-315-6882
NSN 5920-01-366-1517
NSN 6240-00-877-6206
NSN 5835-01-426-6573
NSN 7035-01-012-5807
NSN 6145-01-532-8805
NSN 5895-01-393-0332
NSN 5965-01-442-0490
NSN 6320-01-220-2264