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 5855-01-364-1005
NSN 5975-01-578-8408
NSN 5965-01-107-8549
NSN 5925-01-479-4984
NSN 6150-00-590-3454
NSN 5915-01-063-7561
NSN 5835-00-918-8169
NSN 5990-01-270-1015
NSN 5960-01-458-7999
NSN 5985-01-589-4535
NSN 6135-01-186-4010
NSN 5996-00-248-9081