Martin Authentic SP Phosphor Bronze 12-String Acoustic Guitar Strings, MA500, Extra Light

Martin Authentic SP Phosphor Bronze 12-String Acoustic Guitar Strings are made with the highest quality bronzed steel core wire and phosphor bronze wrap wire. These strings are engineered with the performer in mind and they will always stand up to rigorous practice and performance schedules. Martin starts with their highest tensile-strength core wire, then tin-plate it on all six strings for added corrosion resistance; because what you don't see matters! When coupled with the highest quality wrap wire, you get consistently true tone that you can count on, song after song.