65 degrees with a stainless steel mills 4F, fine particulate material, particle size 0.2, helix angle of 40 degrees, gold coating. Standard D4 * 10 * 50 * 4, extended specifications D4 * 12 * 75 * 4, D4 * 16 * 100 * 4. 25 major cutting ordinary steel, stainless steel. Adapt to ordinary steel 25-38, Shen Dian hardened stainless steel, gray iron, ductile cast iron black, aluminum, titanium, magnesium and aluminum alloys, nickel-based superalloy materials.