Hands free, automatic tuning at a killer price. Tunes acoustic, electric and bass guitars. Qwik Tune tunes two ways; by a super fast LCD meter and by red and green LEDs that guide you to a perfect tune, even in the dark. In and out jacks allow Qwik Tune to be used "in line" during performance. It has a built-in-mic, and even features a low battery indicator. Powered by a 9v battery (not included).