The Grainger 16N097 is a Westward brand 1/4-inch drive socket set. It contains 15 SAE sockets ranging from 4mm to 14mm and 15 metric sockets ranging from 5/32 inch to 9/16 inch. The chrome vanadium sockets have a black phosphate finish for corrosion resistance. This 30-piece socket set comes organized in a molded case for convenient storage and portability. The case has a hinged lid and socket size markings for easy identification.