Your strings matter. D'Addario's Phosphor Bronze acoustic guitar strings are engineered to serve as the critical link between you and your guitar. Their most popular acoustic guitar strings, EJ's are precision wound with corrosion resistant Phosphor Bronze onto a carefully drawn, hexagonally shaped, high carbon steel core. The result is long lasting, bright sounding tone with excellent intonation. • D'Addario's popular extra-light gauging with an exclusive precision polishing process for reduced finger noise • Smooth, flattened playing surface, superb tone and sustain associated with phosphor bronze strings • 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 .012, .016, Phosphor Bronze Wound .024, .032, .042, .053