This 3-Piece Selfeed Bit plumbers' set comes complete with the most popular sizes of selfeed bits for installing common sizes of pipe. The inside cutting plane shaves the hole radius for a clean, smooth hole. Made from heat treated alloy, these bits are designed for maximum durability and wear resistance. The re-sharpenable cutting edge can be sharpened with a standard file. The replaceable feed screw effortlessly pulls the bit through the material and is reusable promoting longer life.