SureGrip Drive Design drives the side of the fastener, not the corner, to provide increased strength and avoid rounding of rusted or damaged fasteners. Made in the U.S.A., featuring the SK SureGrip hex design, which drives the side of the hex, not the corner. This not only provides increased strength, but also avoids the rounding of rusted or damaged fasteners, which can occur when using a sharp cornered hex tool. Black coating for corrosion resistance.