Ernie's newest innovation, "the strongest guitar strings known to man." Designed with a proprietary, break-resistant blend of a plasma process, plus their Everlast nanotreatment. The result - 70% stronger strings that continue to provide that same select Slinky tone and feel, all while impeding corrosion to boot. The wound strings are made from nickel plated steel wire wrapped around a hex shaped steel core wire. Plain strings are made of specially tempered tin plated high carbon steel to provide a well balanced tone. Roundwound nickel-plated steel Beefy Slinky gauges. Fully backed against corrosion and breakage within 90 days of purchase, with all warranties being handled directly by Ernie Ball via their website, customerservice@ernieball.com . Gauges: .011, .015, .022p, .030W, .042W, .054W.