XL Nickel are the industry standard in electric bass strings with clear fundamentals, booming tight lows, and reliable D’Addario construction. XL Nickel bass strings are made with a high carbon steel core and wound with nickel-plated steel wrap wire, for consistently bright tone and smooth playability, great for a wide variety of bass styles. Made for 5-string basses, 45-130 Regular Light gauge strings takes most popular bass gauge and adds a low B-string.