Medium 6 string set from SP Lifespan series that is the next level in studio performance and provides a rich tone that lasts as long as the inspiration does. Strings are treated for long life, they repel dirt, grit and other environmental elements that can quickly alter the sound of your strings. The treatment is incredibly thin and designed to make strings last longer and sound better. The strings are made with the highest quality bronzed steel core wire and 80/20 bronze wrap wire. Gauges: .013, .017, .026, .035, .045, .056.