Martin FX 80/20 Bronze strings are made with bronzed steel core wire and bronze wrap wire.

It isn't just about flexibility; it's about bending the note till it rings true.
Martin FX strings marry our thinnest core wire to our standard tensions so you stay in control of each and every note. Our FX strings feel soft to the touch, which makes them ideal for beginners. But don't be fooled by comfort! Just ask Tommy Emmanuel who performs with our FX strings night after night around the globe. With FX, you get total flexibility and total control.