Powerbuilt mirror-polished chrome vanadium sockets feature large HV High Visibility size markings for easy size selection. Size callout is forged into the socket wall using a patent-pending process and will not rub off or wear out with use. Socket length exceeds ANSI standards. Center hole punched through for additional working depth. Rubber retaining ring holds plug securely. Beveled opening for easier mating to plug. 100% lifetime warranty.