Torque any fastener with a combination wrench or Allen wrench. This tool fits 6mm (1/4") thru 19mm (3/4") combination wrenches. Also suits 6mm thru 8mm Allen wrenches. Tool is heat-treated steel with black oxide finish. 3/8" square drive is rated for a maximum torque of 90 ft-lbs. (121.5 Nm). Instructions with a conversion table are included.