Self-centering, precision-ground tip won't walk on flat or curved surfaces, stays sharp longer, and drills faster than standard high-speed drills. Made from premium M-2 high-speed steel for increased durability. Black and gold oxide coating provides maximum corrosion resistance. Through-hardened chrome vanadium shaft with shot-peened, double-tempered finish is hot-isostatically pressed to resist breakage and extend bit life. 3-flatted shank on 3/16-inch and above sizes offers exceptional grip on chuck.