D'Addario's heaviest 80/20 bronze set, ideal for heavy strumming and flat-picking / Extra-bright tone mixed with deep and projecting bottom end / Environmentally friendly, corrosion resistant packaging for strings that are always fresh / Made in the U.S.A. for the highest quality and performance / String Gauges: Plain Steel .013, .017, Bronze Wound .026, .035, .045, .056 /