Since its introduction in 1974, D'Addario's Phosphor Bronze Strings stand out for their signature warm and balanced sound. XT Phosphor Bronze take that a step further, boasting improved durability, greater pitch stability, and a longer lifespan. The XT coating offers top-level corrosion resistance while preserving the natural warmth of the uncoated string. The construction of the XT acoustic strings - NY Steel core, phosphor bronze wrap wire, and Fusion Twist technology - allows for greater flexibility in sound with increased resilience, offering a great fit for any acoustic style. The 12-53 tension is a favorite for its perfect balance between playability and tone.