The Planet Waves Chromatic Headstock Tuner precisely tunes guitars, basses and many other stringed instruments utilizing the instrument's vibrations rather than sound - no direct sound or electronic signal is required. Using an optimally positioned, highly sensitive piezo transducer and backlit LCD display, the Headstock Tuner allows you to tune quickly and accurately in noisy or dimly-lit environments where many tuners fail. The compact, lightweight design doesn't add cumbersome mass to your instrument and delivers clear viewing from any angle. Simply clip on and tune up!