Martin MSP4200 Phosphor Bronze Medium Acoustic Guitar Strings use a winding alloy that is ideally suited for making strings that deliver deep, rich basses and clear, bright trebles. Martin strings are high-quality strings designed for daily use. Core and wrap wires must meet strict requirements to make the grade. Martin acoustic guitar strings are wound to precise specifications.
Gauges: .013 - .056
Bronze alloy for brilliance and long life