YG-1 E5977 Carbide Square Nose End Mill, Extra Long Reach, TiCN Monolayer Finish, Finishing Cut, Non-Center Cutting, 37 Deg Helix, 3 Flutes, 4" Overall Length, 0.25" Cutting Diameter, 0.25" Shank Diameter Suitable for high-performance machining on aluminum and other nonferrous materials Extended-reach neck style provides access to recessed areas of the workpiece 37-degree helix angle provides increased cutting action and chip evacuation compared to the standard 30-degree helix Titanium carbon nitride (TiCN) coating lubricates the end mill for high-temperature stability and offers better abrasion resistance than uncoated tools Carbide can run at higher speeds than high-speed or cobalt steel, resisting wear and high cutting temperatures