YG-1 E5250 Carbide Ball Nose End Mill, Uncoated (Bright) Finish, 30 Deg Helix, 4 Flutes, 1.5" Overall Length, 0.125" Cutting Diameter, 0.125" Shank Diameter Suitable for machining on hardened and high-alloy steel, steel casting, chill casting, malleable cast iron, chromium-nickel steel, brass, copper, aluminum with a high percentage of silicon, and abrasive plastic Four flutes produce a better finish than fewer flutes Carbide can run at higher speeds than high-speed or cobalt steel, resisting wear and high cutting temperatures Uncoated (bright) tools have no additional surface treatment or coating for use on a range of materials Ball nose end mills (also called ball end) create contoured surfaces