Satin finish provides corrosion resistance and a slip resistant grip. 12 point flare nut box end allows for fine indexing, helping to improve speed and access. Fits 4, 6 and 12 point fasteners. Flare nut box ends incorporates the TorquePlus™ system. Proto® TorquePlus™ wrenches are ideal for use on stubborn or damaged fasteners, and also on fasteners made from soft materials. 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 TorquePlus™ configuration employs a radius-corner design, shifting contact area and stress away from the fastener corners and distributing contact stresses over a large area of the flare nut box end, minimizing slippage. The TorquePlus™ internal design minimizes fastener rounding, helps to extend fastener life, and allows the user to more easily turn worn, rounded, or rusted fasteners.