.40 mm Cutter Diameter x 3.20 mm Length of Cut Carbide Square End Mill Finisher For Exotic High Temp Alloys, 4 Flutes, AlTiN Nano Coated. Select from as many as 7 flutes in this solid carbide, fully stocked offering of Harvey Tool Variable Helix End Mills for High Temp Alloys - Finishers - Square, which feature a large core and eccentric relief for improved tool life and AlTiN Nano coating for superior hardness and heat resistance