0.500 inches nominal length, w/s: helicopter, mh-53e; engine, aircraft, f100-pw-200 (f-16a/b/c/d); engine, aircraft, f100-pw-100 (f-15a/b/c/d); helicopter, seahawk h-60; jet aircraft start unit; helicopter, search and rescue, hh-60h; helicopter, advance attack, ah-1w; aircraft, (ac-130h, mc-130h, ec-130e, hc-130); helicopter, uscg search and rescue, hh-60j; helicopter, carrier based asw, sh-60f end item identification, 0.375-16 unc class 3a insert size, steel comp 1117 overall material, aisi assn std single material response overall material document and classification, cadmium overall surface treatment

A cylindrical item which may have wrenching and/or driving facilities and/or shoulders. It is designed to be inserted in a drilled, tapped or a pretapped hole, or molded or pressed into soft material to reduce the size of a tapped hole; to provide threads; to add strength, and/or to prevent stripping. It is one of the following: (1) a one-piece, flanged or unflanged, internally threaded item which may have external threads, and/or serrations around the periphery of the collar, designed to engage a serrated lock ring which is not included with the item; (2) a one-piece precision coiled wire; (3) a two-piece item consisting of an internally threaded cylinder and a mating externally threaded part; or (4) a one-piece internally threaded item whose outside diameter is tapered and/or knurled and/or with fin(s). The internal thread of the item may have a locking feature. Excludes:items having a sleeve on on its under portion which can be clinched or crimped. Excludes:bushing,machine thread; nut,plain,knurled; nut,plain,round; nut,plain,clinch and nut,self-locking,clinch. See also nut,plain,plate