The Grainger Approved Square End Mill Single End is a high-speed steel end mill with a square end for milling slots, keyways, and pockets. It has 4 flutes and a right-hand spiral. The overall length is 3 inches and the shank diameter is 1/2 inch. The mill diameter is 1 inch with a 1/8 inch shank reduction. It can machine steel, stainless steel, cast iron, aluminum, copper, brass, bronze, plastics, and other non-ferrous metals. This is a high quality end mill made in the USA.