Foldable Piano Keyboard Rechargeable LED Display 128 Tones 128 Rhythms MIDI Output Support 14 Demo Songs 88 Keys Electronic Hand Roll Piano Item Type: 88 Keys Roll Up Piano Material: Silicone, ABS Colour: Black and white Battery Type: 2200mAh lithium ion battery (built in) Power Supply: Rechargeable lithium battery power or USB 5V power supply or mobile charger power supply Keyboard: 88 standard keys (black keys included) Tones: 128 types Rhythms: 128 types Demonstration songs: 14 Functions: Bluetooth connection, reset function, transpose function, easy recording, editing, playback, sustain, vibrato, teaching, chord function Display: LED digital tube display Speaker: Self contained speaker to play independently External: Support for external sound or headphones, can be connected to an external sustain pedal. MIDI Output: Support MIDI output to connect with computer or tablet.