A cylindrical item which may have wrenching and/or driving facilities and/or shoulders. It is designed to be inserted in a drilled 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 its underportion 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.
Dept. of the Navy 
Italy Classification: Press-fasteners, snap-fasteners & press-studs & parts therefor
NSN 5915-01-222-5995
NSN 5960-01-567-1096
NSN 5920-00-931-7979
NSN 5990-00-763-5526
NSN 7035-01-003-7769
NSN 5965-01-444-1322
NSN 6145-01-021-5346
NSN 6105-00-165-4236
NSN 5985-01-013-9044
NSN 5996-01-159-9089
NSN 6105-00-401-2149
NSN 6220-01-175-1246