Made of chrome vanadium steel shank for enormous strength, for use with Tapcon fasteners. Special negative back grinding enables the tip to bore through applications such as masonry, ceramic tile, concrete, brick, fiberglass, plexiglas, cast metals, hardened steel, granite, marble, woods and plastic with a filing action rather than a cutting action. Requires no center punch, eliminates walking and can be re-sharpened. NOTE: not recommended for use on mild steel, e.g. aluminum, angle iron, copper, galvanized pipe, brass and stainless steel. Conforms to ANSI standards.