"The "high-octane" nickel-plated steel strings for your bass. With a pure steel wrap, the magnets in your pickups use the whole string (not just the core) and transform the energy into high output bursts of sound. The nickel plating enhances feel and reduces "string squeak" and fret wear without compromising tone. We use them exclusively on our U.S. Vintage Series basses built in Corona, CA. Offered in 4-, 5- or 6- string versions, these are our most popular bass strings."