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 a 1/2" shank diameter, 1" overall length, and a 1/2" cutting diameter. The end mill has 4 flutes and a right-hand spiral. It is designed for use on steel, stainless steel, cast iron, aluminum, copper, brass, bronze, plastic, and fiberglass at speeds up to 2000 SFM. This end mill is made in the USA.