Features: Mini clip-on tuner, suit for bass, guitars, violins, chromatics, ukuleles and some other string instruments. 360°swivel rotation design, easy and convenient to use -- place the tuner where the vibrations are most pronounced. The automatic shut-off function when no operation for about 5 minutes, to extend the working life of the battery. Easy operation -- the string number and note name will be showed on the LCD screen toghther while tuning; two-color backlight, green light means in tune, blue light means out of tune. The last parameter setting is memorized automatically at startup, and the initial setting is automatically restored after reinstalling the battery. Specifications: Tuning: Chromatic, Guitar, Bass, Ukulele, Violin Tuning Way: Vibration pickup Tuning Range: A0(27.5Hz) - C8 (4186.0Hz) Tuning Precision: ±1 cent Calibration: A4=440Hz Power Supply: 1 * CR2032(not included) Item Weight: 20g / 0.71oz Package Size: 7.8 * 4.3 * 3.2cm / 3.07 * 1.69 * 1.26in Package Weight: 26g / 0.92oz Note: The button battery is not included. Package List: 1 * tuner 1 * operation manual