All-purpose impact sockets are for loosening and tightening fasteners with impact power tools. They have an enclosed head that fits around and grabs the full head of the fastener so the socket doesn't slip off. They can apply more torque than a hand drive tool and have an enclosed head that fits around and grips the entire head of the fastener so the socket doesn't slip off. For secure attachment to the drive tool, impact power wrenches have a square nub called the drive that fits into the same size drive end of the socket. The sockets are designed to securely attach to the impact tool, preventing the socket from flying off the impact wrench's drive during usage. When rotating a fastener, they can handle the higher torque and vibration created by an impact power wrench.