This is a chromatic clip-on tuner that can be used for any instrument, it tunes in keys C, Bb, F, Eb, and D! If you need to tune your instrument in a loud environment, no worries! When this tuner is clipped on it can pick up vibrations to help you tune where ever, whenever. It also has a strong and accurate built-in microphone if you want to tune via sound. It has a pitch calibration range of 410-489 Hz and is battery-powered (one battery included). This tuner has an easy-to-read screen that displays a meter that turns green when the note is played in tune.