High-speed steel square end mills offer good wear resistance for basic milling applications. They're more flexible and can absorb more shock and vibration than carbide, powdered-metal, or cobalt end mills. Sometimes called square-nose end mills, square end mills have a square nose and are rotated against a piece of stock to create a flat-bottomed groove with 90° inside corners in milling tasks. They are used for counterboring, side and face milling, and milling square shoulders.