Sunex 318uz 3/8-Inch Drive 9/16-Inch 12-Point Universal Impact Socket Forged from the finest chrome molybdenum alloy steel-the best choice for strength and durability Radius corner design - to extend the life of fasteners The design drives the side of the fastener instead of the corner 3/8-Inch drive 9/16-Inch, 12 point universal impact socket