Martin SP 92/8 Phosphor Bronze Medium Acoustic Guitar Strings are named "Superior Performance" for a very good reason. For a company who are no strangers to innovation, their SP Phosphor Bronze strings are endowed with some impressive specs. By employing the highest tensile-strength wire at the core of the string with tin-plate, the SP series boast excellent corrosion resistance. The high-quality phosphor bronze wrap wire produces a warmer, mellower tone than that of the traditional bronze string, offering a different tonal quality to suit individual tastes. The Medium gauge of the 13-56s make them ideal for strummers who like to belt out a tune with gusto. Whatever style of music that you're performing and whether you're a soloist or ensemble player, this medium gauge set will ensure that you are heard loud and clear. Each string rings out beautifully so you can rest assured that the subtle nuances of your performance will shine through. From busking on the street to playing in an intimate venue to a festival stage, Martin's SP acoustic guitar strings allow you to sparkle anywhere the music takes you. Established way back in 1833, Martin have a wealth of experience when it comes to their craft. They are continually evolving to ensure that they are at the top of their game, and the SP 92/8 Phosphor Bronze Medium acoustic guitar strings set a fine example for others to follow.