Combination WrenchHandy, two-in-one tool provides convenient task-specific versatility. ASD crescent end features a unique locking groove that prevents fastener slippage, virtually eliminating nut and bolt rounding. Torqueplus™ box end allows you to get up to 15% more force on problem joints. Arched surface enhances force distribution, minimizing the potential for stress-point fractures. Strong, satin-finished chromium-vanadium steel stands up to the rigors of heavy use. Wrench Type: Combination; SAE/Metric: SAE; Opening Size: 9/16".