2.50 mm Cutter Diameter x 7.50 mm Length of Cut Carbide Square End Mill For Aluminum Alloys, 3 Flutes, TiB2 Coated. Optimized for aluminum and aluminum alloys with excellent performance in copper, brass, and bronze alloys, Harvey Tool's Variable Helix End Mills for Aluminum Alloys - Square reduces chatter and harmonics, and improves material removal rates (MRR).