Designed for rotary or percussion drilling. Drills through hardened steel, ceramic tile, marble, plastic, cast metal, concrete, glass, plexiglass, granite, fiberglass, brick, masonry, PVC (polyvinyl chloride) and wood. Requires no center punch - eliminates walking. Negative back grinding enables tip to bore through materials with a filing action. Cobalt and tungsten carbide drill bit tip designed for maximum hardness, wear and resistance to heat up to 2000 F (Degree Fahrenheit). Resharpenable on silicon carbide grinding wheel. Chrome vanadium steel shank for strength and flexibility. Bit has a flat bottom parabolic flute for faster waste removal. Conforms to ANSI (American National Standards Institute) standards. null -