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 6650-01-221-0356
NSN 6320-01-209-0952
NSN 6105-01-152-2800
NSN 6240-00-185-8367
NSN 5835-01-475-3101
NSN 5975-00-370-9388
NSN 7035-01-454-3284
NSN 5996-01-440-9660
NSN 5855-00-995-2098
NSN 6620-00-004-5466
NSN 6685-00-222-1306
NSN 6110-01-108-9055