1/4” DRIVE, STUD SETTERThe Stud Bolt Setter is a special socket for installing a stud bolt. The bolt contact with a steel ball to prevent the bolt from sticking onto the socket. After installing the bolt, turn anti-clockwise to remove the socket. Input Drive Size: 1/4" Drive Shape: Hex Length: 66mm Type: Stud Setter Op 1/4 Hex Dr. Stud Setter 1/2 Length 66mm