577-2629SW Features: -Box opening remains on fastener when wrench is struck. -Efficient transmittal of force to fastener. -For where extreme force is needed to loosen or set large fasteners. -Heavy box walls provide greater torque transmission. Use: -Box End Wrench/Striking Wrench. Quantity: -Single. Number of Points: -12. Measurement Type: -SAE. Product Type: -Wrenches. Dimensions: Overall Product Weight: -6.2 Pounds.