Cobra Carbide regular length straight flute drill bit is made of micro grain solid carbide. The added web strength of the straight flutes and 140 degrees special point configuration easily penetrate work pieces with minimal deflection. For use in hardened, treated and abrasive materials, as well as stainless steel and cryogenic alloys. Designed to be used in hardened steel, stainless steels, and other exotic materials 38-40 Rockwell "C" scale. Accurately sized holes are produced without annealing or softening the workpiece Reamer type finishes are easily produced. Good working on carbon steel, nickel/inconel alloy, titanium. Excellent working on alloy steel, hardened steel, stainless steel. Tolerance: H6 - shank diameter; H7 - cut diameter.