Wireless Bluetooth trolley speaker with LED display ? Digital Karaoke ? Professional treble & bass gain controlling circuit ? Built-In professional wireless microphone system ? Built-in MP3 encoding support ? Connection Type: Bluetooth, USB, FM Radio, TF card, Aux in port, Mic In ? Compatible with DVD/PC and other sound sources ? Intelligent power switch charging circuit ? User-friendly Trolley ? 8 meters Operating Range ? Up to 4.5 hours of Playback ? Battery capacity: 2200 mAh ? Total Output: 40W RMS ? Controls: Volume, Mode and Track Controls ? Subwoofer Size: 8 Inch ? Colours Available: Black