The Planet Waves Piezo Tuning Clip aids in the tuning of acoustic instruments with or without electronics. To use, simply attach the Piezo Tuning Clip to a vibrating surface of the instrument such as the headstock or bridge and plug the ¬? plug into the input of your electronic tuner. The Piezo Tuning Clip will transfer the vibrations directly from the instrument to your tuner. This allows you to tune instruments with greater ease and accuracy, especially in noisy environments. Planet Waves, part of the D'Addario family of brands, is known for innovative, problem-solving, quality musical accessories. Planet Waves offers a complete line of award-winning accessories including cables, picks, tuners, capos, straps, humidifiers, maintenance tools and more.