Double-end corner-radius end mills have a nose on both their ends and can accomplish more milling tasks than single-end end mills before they need to be replaced. When the cutting edges on one nose wear down, the end mill can be flipped over to expose the fresh cutting edges on the other nose. Sometimes called bull-nose end mills, corner-radius end mills have a square nose with slightly rounded corners that help distribute cutting forces evenly to prevent damage to the end mill and extend its life. They are rotated against a workpiece to create a flat-bottomed groove with slightly rounded inside corners in milling applications that require a specific radius.