This heavy duty 3/8" square drive impact socket set is designed for daily use with air driven impact wrenches and ratchets. 3/8" sq. dr. deep sockets 8 10 11 13 14 16 17 18mm. 3/8" sq. dr. deep sockets 3/8" 1/2" 9/16" 11/16". Made from top quality chrome vanadium steel