The J4601 is the perfect replacement string for the D'Addario EJ46 Pro-Arte Hard Tension classical guitar string set. Pro-Arte, the world's most popular classical strings are D'Addario's premium classical guitar string sets. All Pro-Arte treble strings are sorted by a sophisticated computer-controlled laser machine which performs diameter and tension measurements, ensuring true-sounding, precise trebles in every set. Pro-Arte basses are wound using silver-plated copper on a multi-filament nylon core for consistent and warm, yet projecting tone.D'Addario, the world's largest manufacturer of musical instrument strings, is known as The Players Choice with a reputation for unsurpassed quality and consistency. D'Addario's innovative, environmentally friendly packaging reduces waste and provides protection from corrosion. All D'Addario strings are manufactured in the U.S.A. using proprietary, digitally controlled, state-of-the-art machinery for unmatched performance, set after set. The perfect replacement string for the D'Addario EJ46 Pro-Arte Hard Tension first string Laser sorted clear nylon treble strings for consistent, precise intonation Hard Tension Perfect as a replacement string or for custom sets Made in the U.S.A. for the highest quality and performance