Martin SP Lifespan Phosphor Bronze acoustic guitar strings are made with bronzed steel core wire and phosphor bronze wrap wire, then and all six strings are treated for long life.
• Treated with Martin's Clear tone proprietary technology for a longer lifespan than regular strings
• Designed to repel the oils and dirt that can deaden strings
• 92/8 phosphor bronze provides a classically expressive tone
• Gauge (custom light): .011, .015, .023, .032, .042, .052