The Grainger Approved Square End Mill Single End Carbide is a milling cutter with a square end for machining slots, keyways, pockets, and contours in aluminum, brass, bronze, cast iron, steel, and stainless steel. It has four flutes and is made of solid carbide with a TiAIN coating for wear resistance and heat dissipation. The shank diameter is 3/8", overall length is 2-1/2", and cutting diameter is 1/2". It has a center cutting design for plunge cuts and should be run at speeds up to 8,000 RPM with conventional high speed steel speeds and feeds.