The Wilson Sensation tennis string has a gauge of 16 (1.30mm) & is supplied as a 12.2m (40ft) long set that enables you to re-string one racket. The string is available in a natural colour & has a multifilament core that offers excellent comfort to people suffering from tennis elbow or other arm problems. It incorporates highly elastic nylon fibres that impart power & reduce vibrations to further enhance comfort.