ERNIE BALL 2003 MEDIUM LIGHT EARTHWOOD 80/20 BRONZE ACOUSTIC GUITAR STRINGS 12-54 GAUGE Ernie Ball Earthwood 80/20 Bronze Acoustic Guitar Strings are made from 80% copper, 20% zinc wire wrapped around hex shaped brass plated steel core wire. These acoustic guitar strings provide a crisp, ringing sound with pleasing overtones. .012, .016, .024w, .032, .044, .054 Thanks for checking out our online store! 🎸 Be sure to visit us in person in sunny Phoenix, AZ!