Gauges: .065-.075-.100-.115. Long scale. The RS88LD Trubass Black Nylon Flatwound Bass Strings were originally developed to simulate a double bass sound on an electric bass. These RotoSound strings made their most famous appearance on top of the 'Apple' building while Paul McCartney was playing his Hofner bass. You will note that the tension is low, making this string extremely comfortable to play.