Next generation Martin Authentic Acoustic Lifespan 2.0 strings are engineered using a new, patented anti-corrosion treatment only available from Martin. It protects the core and wrap wire to prevent corrosion without compromising tone or feel. Martin's impeccable standards for acoustic guitar tone are imbedded in their string design and precision manufacturing process.

MA550T String Gauges: .013, .017, .026, .035, .045, .056
Tension: 190.9