D'Addario EJ49 Pro-Arte Black Nylon Classical Guitar Strings, Normal Tension D'Addario's best selling Pro Arte set, Normal tension offers balance of volume and comfortable resistance Laser sorted black nylon treble strings for consistent, precise intonation Precision wound basses for warm, projecting tone and the utmost consistency Made in the U.S.A. for the highest quality and performance String Gauges: Trebles .0280, .0322, .0403 Basses .029, .35, .043