Terence Digital Metronome for Piano Guitar Drum and All Musical Instruments Electronic Metronome with Volume Rhythm Adjustable Rechargeable Metronome with Speaker Timer Function LCD Display. Compared with traditional metronome the innovative version of metronome has a built-in rechargeable battery which can be played not only at home but also in outdoor performances outdoor concerts and other places where power supply cannot be guaranteed. The built-in upgraded chip brings better performance experience to you. It is equipped with LCD display which not only shows the battery charge at a glance but also clearly shows the beat rhythm type timer and beat speed