For rotary and percussion drilling Chrome vanadium steel shaft and shank provides extra hardness and enormous strength No center punch required eliminates walking Cobalt and Tungsten carbide tip for max hardness and resistance to heat and wear High tech bonding allows bit to withstand drilling temperatures up to 1 900 degrees Fahrenheit Easy to resharpen For use in hard hitting impact tools Black Oxide finish Conforms to ANSI standards NOTE Not recommended for use on mild steel This includes alu-Tools/Power Tools/Accessories/Drill Accessories/General Purpose Drill Bits