Aquila 19C Normal Tension Alabaster Series Classical Guitar Strings. The Aquila 19C Normal Tension Alabaster Series are a set of classical guitar strings composed of the first three strings made of Supernylgut monofilament and the three bass consisting of a Supernylgut multifilament core spun in silver copper, normal tension, with a scale of .066 .081 .096 .070 .086 1.06 mm
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