An American National Standard. The American Society of Mechanical Engineers (ASME). Revision of ASME B1.3М-1992. Date of Issuance: October 12, 2007. 22 р. This Standard presents screw thread gaging systems suitable for determining the acceptability of UN, UNR, UNJ, M, and MJ screw threads on externally and internally threaded products. It establishes the criteria for screw thread acceptance when a gaging system is used