Martin Authentic SP Acoustic Guitar Strings, 80/20 Bz, Bluegrass, 12-56 - MA240

Bluegrass. 012. 016. 025. 035. 045. 056 (179.8 Tension) MA240. Martin® Authentic Acoustic® Superior Performance SP® strings feature higher tensile strength and tin-plated core wire on all six strings that enable a fuller and more balanced tone, quicker response and increased tuning stability.

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