YG-1 E2170 Cobalt Steel Square Nose End Mill, Weldon Shank, Uncoated (Bright) Finish, Roughing Cut, Non-Center Cutting, 30 Deg Helix, 3 Flutes, 2.4375" Overall Length, 0.25" Cutting Diameter, 0.375" Shank Diameter Roughing end mills have chip-breaking cutting edges that remove material in less time than conventional end mills Coarse-pitch tooth design and tool geometry are suitable for machining cutting-steel grades and many nonferrous materials Number of flutes varies by diameter for optimum feed and cut rate Cobalt steel resists abrasion and high cutting temperatures, and has higher feed rates than high-speed steel Uncoated (bright) tools have no additional surface treatment or coating for use on a range of materials