Torx head screws resist cam-out better than Phillips head or slot head screws.Whereas the tendency of Phillips drivers to cam out under excessive torque has been listed as a feature preventing damage to the screw-head or driver, Torx heads were designed to prevent cam-out. The development of better torque-limiting automatic screwdrivers for use in factories allowed this change. Rather than rely on the tool to slip out of the screw head when a desired torque level is reached (which risks damage to the driver tip, screw head, and/or workpiece), torque-limiting driver designs achieve a desired torque consistently.
The Torx design allows for a higher torque to be exerted than a similarly sized conventional hex socket head without damaging the head and/or the tool. The diagram depicts the interaction between the male and female components of a conventional hex drive and a Torx drive. The clearance between the components is exaggerated for clarity.
