MIL-T-21309E, MILITARY SPECIFICATION: TOOLS FOR INSERTING AND EXTRACTING HELICAL COIL WIRE SCREW THREAD INSERTS (28 FEB 1975) [S/S BY A-A-59158]., This specification covers taps, thread plug gages, inserting tools, expanding tools, offset and staking tools, and extracting tools for inserting and extracting helical coil wire screw thread inserts.