Purpose built for demanding metalworking, fabrication, installation, and machining jobs. Precision machined 1/4 hex shank adapter for use with 3-jaw chucks, quick change chucks, or impact drivers. Sturdy, screw machine length HSS twist drills are made in the USA and have a heavy-duty surface treatment for increased wear resistance and edge toughness. 135° split point resists walking for accurately located holes and fast penetration, ideal for punch drilling" in hard, tough sheet metal. Our signature gold set screw and locking flat on the twist drill ensures slip free drilling.