12-54 Martin MA540T Authentic Acoustic Lifespan® 2.0 Guitar Strings Phosphor Bronze

"Next generation Martin® Authentic Acoustic® Lifespan® 2.0 strings are engineered using a patented anti-corrosion treatment only available from Martin. It protects the core and wrap wire to prevent corrosion without compromising tone or feel. Our impeccable standards for acoustic guitar tone are embedded in our string design and precision manufacturing process. That’s why we make our own."

- Martin