Features and Benefits:Includes 6-point shallow, deep and universal impact sockets from 7 mm – 22 mm, 3 in. extension and 3/8 in. drive universal joint3/8 in. drive x 1/4 in. hex shank adapter included for use with cordless impact toolsRadius corner hex design maximizes socket durability while limiting fastener wear over timeAll socket forged from high quality CR-MO alloy steel This is an impact Socket set. It has 51-Pieces. It is 3/8 in. drive.