Ernie Ball 2144 EARTHWOOD Acoustic Guitar Strings Ernie Ball Slinky 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. 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. Features: Model: P02144 Pruduced with an exclusive phosphor bronze wrap wire Engineered to meet the demands of acoustic musicians worldwide Made with the finest and freshest raw materials, all Ernie Ball Strings are hermetically sealed to ensure your stirngs stay as fresh as the day they were made. Made from 92% copper, 7.7% tin, 0.3% phosphorus wire wrapped around tin plated hex shaped steel core wire. These guitar strings have a light orange, gold color and provide a mellow, ringing sound, with excellent clarity. 13-17-26-34-46-56 Made in the U.S.A 4 Sets of Strings