The Martin Guitars MA540S Acoustic Marquis Silked Strings for Western Guitar have been reworked from the ground up with the latest technology. The new "Acoustic Marquis Silked" strings have an extended life span with optimal sound and constant quality. The silk wrapping at the ball end protects the wood of the bridge from wear and tear. The MA540S Acoustic Strings are made of 92/8 Phosphor Bronze and are corrosion resistant. Due to the own string production the strings are optimally tuned to the Martin guitars.