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 SureGrip hex design, which drives the side of the hex, not the corner. Coated with a rust-preventative compound that makes them exceptionally resistant to corrosive factors. Laser engraved with 3 extra large markings every 120 degrees around the sockets for improved readability.