Champion DT22HEX-SET10 Combination Drill and Tap Set, 10-Piece Tapered neck design significantly reduces drill & tap breakage The 135 degree split point drill permits holes to be cut at high speeds. Taping caution must be adhered to with slower speed. Superior strength durability provided by high Molybdenum content and high speed steel with functional black and gold surface treatment that holds lubricant for smoother drilling. Applications include: Construction, Electrical, Maintenance, Industrial, Automotive, Farm Implement Machinery, HVAC. Cuts steel, cast iron, aluminum, bronze, brass, zinc and some stainless steel. Contents include: 6-32, 8-32, 10-24, 10-32, 12-24, 1/4-20, 5/16-18, 3/8-16, 7/16-14, 1/2-13