The Ernie Ball Acoustic Guitar String Tone Pack is the perfect way to experience three legendary acoustic tones. From the ever-popular Earthwood 80/20 Bronze strings, featuring a crisp ring, or the Earthwood Phosphor Bronze Strings, providing warm and rich overtones, to Ernie Ball's exclusive Aluminum Bronze Strings, which give your guitar more projection and clarity than ever before. Three tones. One Pack. Perfectly wound for any sound.