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 6645-01-539-0939
NSN 5950-00-419-3599
NSN 6105-01-361-8352
NSN 6620-01-171-2505
NSN 5990-01-162-9220
NSN 5999-01-085-4305
NSN 6145-01-484-8735
NSN 5998-00-203-1232
NSN 6620-01-255-7757
NSN 5895-00-050-2044
NSN 7035-01-397-5009
NSN 5990-01-408-6142