Features: 1. No need to worry about changing the battery. The internal rechargeable battery can be recharged 500 times. The tuner constantly monitors the power volume and alerts you by displaying the power volume symbol on the screen. This rechargeable tuner can be quickly charged in as little as 1.5 hours using the USB cable (included in the package) for up to 5.5 hours of continuous use. Automatically power off after 3 minutes of no signal, thus saving energy. Save your money and protect the environment. 2. Tune your instruments more precisely. The new feature of the on-screen cent indicator shows how many cents away from the note. 3 cents more or less, showing the note being tuned. So keep your instrument tuned for just 3 cents away and 3 less from the tuner. Use the same tuner for multiple instruments. The tuner has built-in high-sensitivity piezoelectric sensors that pick up a wide frequency range, especially low frequencies, and can quickly and accurately tune musical instruments such as acoustic electric classical and steel guitars, 7- and 12-string guitars, ukuleles, Mandolin, banjo and bass guitar. With pitch calibration from 430Hz to 450Hz, you can easily and quickly tune the instrument at different pitches. Clear, bright, colorful graphics make it easy to see if you're out or tuned in from any angle in different lighting conditions. Dual 360-degree rotatable clips are flexible enough for right-handed and left-handed musicians to read the screen from any angle.