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 5985-00-928-8242
NSN 5930-01-442-6723
NSN 6135-01-122-4448
NSN 6620-01-137-1176
NSN 5920-01-284-8679
NSN 5935-00-596-1755
NSN 5930-01-057-3222
NSN 6105-01-012-0965
NSN 5950-00-179-2358
NSN 6610-01-440-9913
NSN 6650-00-187-5388
NSN 5998-00-280-2733