10 piece set is made in the U.S.A., featuring the SK's High Visibility technology. The sockets are coated with a rust-preventative compound, which makes them exceptionally resistant to corrosive factors. In addition to the rust-preventative coating, the sockets are laser engraved every 120° with extra-large markings for improved readability.SureGrip® Drive Design drives the side of the fastener, not the corner, to provide increased strength and avoid rounding of rusted or damaged fasteners.Corrosive resistant and laser engraved every 120 degrees1/2" Drive Swivel Impact Sockets - 10MM, 11MM, 12MM, 13MM, 14MM, 15MM, 16MM, 17MM, 18MM, 19MM