CHROMATIC TUNER Rechargeable tuner- Works for electric, acoustic, bass, banjo and ukulele guitars- Mounts discreetly behind the headstock of the instrument, is virtually invisible to the public- Lights up very quickly- No buttons, turns on and off when you play the plane- It also has an auto-off if it does not receive vibration from the strings- Rotating circular screen to put it where it is best seen- You can customize the orientation of the display or the note- LEDs indicating the battery level- USB charging cable included- Titanium shielding to eliminate background noise- Tunes by vibration- Pitch reference A=440Hz