Pro Arté is D'Addario's best-selling classical guitar string. Appreciated for its perfect balance of tone, playing feel and dynamics. Several years of development led to the Pro Arte series, where the diameter of each strand is checked 200 times using a sophisticated computerized laser system. This extremely careful quality control guarantees an absolutely consistent and high standard of the strings from set to set. The bass strings are precision spun with a silver-plated copper wire over a nylon core, which gives the string its warm and clear tone. According to many concert guitarists the best string set ever created, and highly recommended by most guitar teachers. * D'Addario's most popular classical guitar string. * Laser-controlled guarantees absolutely consistent quality. * Precision spun bass strings for warm and clear tone. * Normal Tension. * String gauges: Trebles .0280, .0322, .0403 Basses .029, .35, .043. * Made in the USA.