Portable 88 Keys Electronic Keyboard Hand Rolling Up Piano Built in 1100mAh Li On Battery Features: Supports recording, programming, playback, tutorial, sustain and vibrato functions. 14 demo songs, 128 kinds of rhythms, 128 kinds of tones for easier practice. LED display shows the relevant parameter information clearly and intuitively. Built-in speaker and headphone jack for connecting earphone or external speaker. With USB MIDI output interfaces to support computer or tablet connecting.  Specifications: Condition: Color: Black + White Material: Silicon + Plastic Keyboard: 88 keys Tone: 128 Rhythm: 128 Demonstration songs: 14 Power Supply: USB 5V Power Adapter(Not included) Battery: Built-in 1100mA Li-ion Battery Main body size: 23 x 9.5 x 2.5cm / 9.1 x 3.7 x 1in Keyboard size: 125 x 16 x 1cm/ 49.2 x 6.3 x 0.4in Total Length: Approx. 133cm / 52.4in Weight: Approx. 1725g Packing List:  1 x Rolling Up Piano 1 x Pedal 1 x USB Cable 1 x User Manual Note:Use the front keys to roll back along the control box, and use them after tapping the keyboard flat.