for Soprano, Concert and Tenor ukuleles AQUILA Single Low A/G ukulele string - RED series The Red Series is Aquila's high-tech string combining the elasticity of Nylgut with the durability of a heavy copper coating. The RED SERIES offers a unique look and a strong, consistent sound. Until the Red series, it was necessary to increase a string’s gauge, or diameter, to reach lower frequencies. But increasing the string’s diameter also increases internal dampening, making the string less bright, less responsive and more muffled; the thicker the string, the duller the sound. Aquila's revolutionary new approach changes the specific weight of the material, increasing it progressively to leave the gauge unchanged. The result is amazing—the instrument sounds brighter, more powerful and more responsive through the entire range of the fret board. The strings also maintain their intonation better (because thicker strings need to be fretted harder, pulling them farther out of tune). Until now, this result was reached only with harps where the scale of the strings is continuously varied. A RED SERIES Low A/G string provides superior performance over a traditional string for musicians who love a clear, sharp sound and powerful voicing. Please note that although the package is marked "Tenor Red Series Sing. 4th.", this string will fit ukuleles ranging in size from soprano to tenor.