Black Oxide drill bits are manufactured from industrial high speed steel, surface treated for high performance and long life, Also no center punch needed: Mountain Quick-cut points are self centering and penetrate faster with less pressure, will not ""walk"" or ""wander"" at the starting surface, 3/8"" reduced shank, Black Oxide treated for wear resistance and greater lubricity, Made from premium grade high speed steel, 135 Degree split point, Designed to drill common steel (flat bar, angle iron, tubing), wood and plastic, Manufactured to Aerospace NAS 907-B specifications, Size: 31/64"", SKU: ISN15024