This JOYO JMT-01 tuner & metronome is designed with color display to indicate how close the note is to in tune. The color screen can rotate 360 degree for easy viewing. This tuner is packaged with a battery for power source. It can automatically power off if no operation for 3 minutes.Specifications: Function:JOYO JMT-01 360 Degree Rotate Clip On Tuner & Metronome with Color Display Feature: - Has tuner， metronome and TAP tempo metronome functions. - Easy to read with full color display， and the color display can rotate 360 degrees for viewing. - Supports MIC and CLIP tuning modes. - Can stand on a flat surface or clip onto the instruments. - More accurate， high sensitive and wide tuning range. - Packaged with a CR2032 battery， power off automatically after 3 minutes for saving the battery if no operation. Brand: Joyo Model: JMT-01 Tempo: 30 ~ 250bpm TAP Tempo Range: 30 ~ 250bpm Tuning Range: 410 ~ 450Hz Tolerance: + / - 1 cent Tuning Range: 0A(27.5Hz) ~ 8C(4186.01Hz) Tuning Mode: MIC， CLIP Tuning Item: c-chromatic， g-Guitar， b-Bass， v-Violin， u-Ukulele Screen Color Modes: - Flat: Yellow - Sharp: Yellow， Blue， Red - In Tune: Yellow， Blue Power Source: 1 x CR2032 Battery Color: Black & Green Product Weight: 30g Package Weight: 44g Product Diameter: 44mm Product Height: 70mm Package Dimensions (L x W x H): 55 X 32 X 80mmAccessories: 1 x User Manual 1 x CR2032 Battery