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 5965-00-671-4119
NSN 2925-00-265-7539
NSN 6645-01-258-6188
NSN 5925-01-088-6863
NSN 5915-01-555-8081
NSN 5950-01-633-2949
NSN 2925-01-327-3069
NSN 6645-01-505-1516
NSN 5965-01-593-2740
NSN 6240-01-538-3727
NSN 6650-00-973-6945
NSN 5835-01-099-4573