Korpa 
EJ44, extra hard tension, is optimal for maximum string resistance and projection without compromising tone.
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.
- Extra hard tension for maximum volume and resistance
- Laser sorted clear nylon treble strings for consistent, precise intonation
- Precision wound silver-plated basses for warm, projecting tone and the utmost consistency
- Made in the U.S.A. for the highest quality and performance
- String Gauges: Trebles .0290, .0333, .0416 Basses .030, .036, .045
- Environmentally friendly, corrosion resistant packaging for strings that are always fresh
