Product Features High-precision LCD needle-type meter Calibration function lets you specify concert pitch Built-in high-sensitivity mic Auto power off This compact chromatic tuner supports a broad range of C1 (32.70 Hz)-C8 (4186.01 Hz), allowing speedy and high-precision tuning of wind, string, keyboard, and other instruments. This tuner is ideal for tuning even low-register notes containing numerous overtones that are often difficult to tune.