EJ45C, normal tension, is D'Addario's best selling "composite" set, preferred for its balance of bold, yet warm tone, comfortable feel and dynamic projection. Pro-Arte composite strings feature an exclusive multifilament stranded core material which delivers a powerful, but warm tone which lasts 2-3 times longer than traditional classical strings. In addition to three traditional nylon treble strings, each set contains an optional monofilament composite 3rd/G string, which provides greater projection and optimal balance between basses and trebles. All Pro-Arte treble strings are sorted by a sophisticated computer-controlled laser machine which performs diameter/tension measurements and quality checks, ensuring true sounding, precise trebles in every set. Silver plated copper wound on an exclusive Composite core material for powerful, long lasting tone Composite 3rd/G for increased projection, clear nylon 1st and 2nd strings. All laser sorted for consistent, precise intonation Normal tension offers popular balance of volume and comfortable resistance Made in the U.S.A. for the highest quality and performance String Gauges: Trebles .0280, .0322, .036 Basses .028, .35, .044