Rotosound is a company with a lot of history and they are made in England. They are an 80/20 Bronze alloy, made with the highest quality copper and tin. They are bright and crisp, they are smooth and easy to bend. Their brass wire covers offer the resonant advantages with considerable clarity & tone. The tone can be described as good mid ranges with brilliant high overtones, a very nicely balanced string. 80/20 bronze Bright and crisp tone nicely balanced string Gauges: TB10 Gauges 10-14-20w-28w-40w-50w TB11 Gauges 11-15-22w-30w-42w-52w TB12 Gauges 12-16-24w-32w-44w-54w