Features: This is two in one: tuner & metronome. Digital Tuner is more accurate very sensitive and wide . It has tuner metronome and TAP tempo metronome functions. Can rotates 360 degrees for easy view. It can stand the unit on a flat surface or clip this unit on a flat surface or instruments so it supports MIC and CLIP tuning modes. Powered by one CR2032 button battery (NOT INCLUDE). Tuning for Chromatic Guitar Bass Violin and Ukulele. Specifications: Tempo: 30-250 bpm Tap Tempo: 30-250 bpm A4 Frequency: 410-450Hz Tuning: 0A(27.5Hz)-8C(4186.01Hz) Tolerance: +/-1 cent Tuning Modes: MIC CLIP Package size: 8.2 * 5.7 * 3.5cm / 3.2 * 2.2 * 1.4in Package weight: 45g / 1.59oz Package List: 1 * Clip-on Tuner 1 * User Manual (English & Chinese)