D'Addario J75 Mandolin Strings, Phosphor Bronze, Medium/Heavy, 11.5-41 D'Addario's heaviest gauge mandolin set, ideal for hard driving, percussive playing styles Loopend construction for universal fit Phosphor Bronze for long lasting, warm and bright tone Made in the U.S.A. for the highest quality and performance String Gauges: Plain Steel .0115/.011.5, 016/.016, Phosphor Bronze Wound .026/.026, .041/.041