D'Addario EPS520 ProSteels Super Light Gauge 9-42W offer one of the brightest and most magnetic electric guitar strings currently available. D'Addario EPS520 ProSteels Super Light feature a specialized alloy that delivers a harmonically rich, brilliant high-end, with increased crunch and sustain. Each wrap on EPS520 ProSteels come precisely wound onto a hex core using exclusive computer-controlled machines, which monitor wrap speed and tension. The result is strings with precise intonation and unparalleled consistency, set after set.