Using an exclusive phosphor wrap, you get balanced tone with superior clarity. Gauges 11-15-22w-30-42-52 Ernie Ball Earthwood Phosphor Bronze Acoustics are produced with an exclusive phosphor bronze wrap wire. Engineered to meet the demands of acoustic musicians worldwide, these concert quality strings provide deep, rich bass notes with clear bright trebles. Ernie Ball Earthwood Phosphor Bronze Acoustics are played by Paul McCartney, Brad Paisley, and Maroon 5 amongst many other touring musicians. Made with the finest and freshest raw materials, all Ernie Ball strings are hermetically sealed to ensure your strings stay as fresh as the day they were made.