Diminsionslength 1.813 in. Oa; first end threaded 0.500-13unc-3a with wrenching facili type 0.252 in.Min.Wide across flats, chamfired 0.062x45 deg; second end-major diameter 0.507 in., tapered 15 degrees to 0.165 in.Max dizataper length 0.438 in.; 125 machined finish; used on 7.62mm rocket m1a2.