XS is breathing new life into coated strings. With its ultra-thin film coating on every wound string and unique polymer treatment on the plain steels, XS offers our highest level of protection for maximum life with an uncommonly smooth feel, making it the most innovative coated string ever created. XS Nickel coated electric guitar strings provide the longest life of any D’Addario electric guitar string. Coated with our groundbreaking XS coating, these premium electric strings attain maximum life and a smooth, fast feel without dampening their outstanding tone. Constructed with a NY Steel core, reformulated nickel-plated steel wrap wire, and Fusion Twist technology, XS Nickel strings boast superior strength and tuning stability, plus richer harmonics, greater clarity, and remarkable definition with every sweep, slide, and bend. This 11-49 Medium gauge set provides increased volume, with slightly more tension and resistance.