Normal tension 6 nylon string set for classical guitar containing silver on nylon wound strings and rectified clear nylon treble strings for highly accurate intonation. D'Addario Pro-Arté Rectified sets utilize our precision rectified nylon trebles - each ground using our proprietary centerless grinding technique. Roundness and dimension control are unsurpassed, ensuring absolutely perfect intonation. Classics are known for their warmer, mellower tone and slightly textured feel. Gauges: .028, .032, .040, .029w, .035w, .043w.