D'Addario XT 12-53 6-String Light Phosphor Bronze Coated Acoustic Guitar StringsSince The D'Addario introduced Phosphor Bronze acoustic guitar strings in 1974, they have been synonymous with warm, well balanced tones. The D'Addario XT Phosphor Bronze Acoustic Guitar Strings offer that and more, boasting enhanced break resistance, better pitch stability, and longer life than the standard phosphor bronze strings. Design and Function The XT coating delivers advanced corrosion resistance, while still retaining the warm tone and