YG-1 E5065 Carbide Square Nose End Mill, Extra Long Reach, Uncoated (Bright) Finish, 30 Deg Helix, 4 Flutes, 4" Overall Length, 0.3125" Cutting Diameter, 0.3125" Shank Diameter Suitable for general-purpose machining on hardened and high-alloy steel, steel casting, malleable cast iron, chromium-nickel steel, brass, copper, aluminum with a high percentage of silicon, and abrasive plastic Extra-long-length end mills have longer cutting edges and can make deeper cuts than long-length end mills 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 broad range of materials