ProSteels are D'Addario's brightest and most magnetic guitar strings. A specialized alloy delivers harmonically rich, brilliant high end, and increased crunch and sustain. Each wrap is precisely wound onto a hex core using exclusive computer-controlled machines that monitor wrap speed and tension. The result is replacement guitar strings with precise intonation and unparalleled consistency, set after set. • MFSKU EPS520 • UPC 019954953973