Precision ground cutting edge with a threaded feed screw tip and a single chip lifter for clean job * For drilling large diameter holes in wood for pipe, conduit and others. * All bits have a 7/16" hex quick change impact shank that fits 1/2" or large electric drill * All bits have a 7/16" hex quick change impact shank that fits 7/16" hex impact wrench drills * Each bit come with an extra screw point and a hex key