This 6 1/2″ long 13/16” 12-point deep socket for a 1/2″ square drive stops the torque loss of using a short standard socket with a socket extension. When using a socket extension, it allows some of the torque from the torque wrench to twist the extension like a torsion bar and not be delivered to the socket that is turning the nut.  The 6 1/2″ length is made so the use of an extension is not required. It is used on head stud nuts, and clutch stand stud nuts. Not for use with an air Impact gun. (rattle guns).