This Draper Japan socket set includes 4 chrome sockets and an extension bar with drive size of 1/2 inches. The set contains a range of sizes including 3/8in, 7/16in, 9/16in and 11/16in. With a brand like Draper, you can be assured of the quality of these tools. Perfect for any DIY enthusiast or professional mechanic, this set is a great addition to any toolkit. These were my sons who was an engineer.