XL Nickel Wound EXL145 electric guitar strings are the standard against which all other strings are measured. Our best-belling electric set, XL Nickel has been revered by players everywhere since 1974. Made with a high carbon steel core and nickel-plated steel wrap wire, XL Nickel strings have a bright, versatile tone, ideal for a wide variety of musical styles. This 12-54 Heavy gauge set is made with a plain steel 3rd/G-string for more flexibility than traditional 12-gauge electric strings.