Torqueplus fastening system drives off fastener body, more easily removing damaged fasteners. Reduces risk of fastener rounding. Anti-Slip Design (ASD) wrench has a locking groove prevents slippage and knuckle injury. Applies more torque to fastener.
From the Manufacturer
The box end of most Proto wrenches incorporate the TorquePlus wrenching system. The TorquePlus design is a high performance drive configuration which allows for quick and easy wrench engagement to the fastener flats, not the corners. The configuration employs a radius-corner design, shifting contact area and stresses over a large area of the wrench, minimizing slippage. The internal design of the TorquePlus minimizes fastener rounding, helps to extend fastener life, and allows the user to more easily turnworn, rounded, or rusted fasteners.