? Ti-coated, #4241 HSS, ? For steel, cast iron, malleable iron, non-ferrous metal and plastic, ? Sizing 1/16, 1/16, 5/64, 5/64, 3/32, 3/32, 7/64, 1/8, 9/64, 5/32, 3/16, 7/32, 1/4, 5/16, 3/8 in.