AMAZ 15' inches rechargeable bluetooth speaker is an all in one portable built-in amplifier rechargeable bluetooth speaker that comes with amazing features such as bluetooth, usb slot, sd card slot, fm 2 wireless microphone radio,antenna for the wireless microphones, music volume, bass volume, treble volume, echo volume, mic volume, mic port (for either microphone, keyboard or guitar ), and external battery socket and on and off switch.there is also a remote control so you can remotely choose your music, control the volume and play/pause. it has movable tyres with trolley hand.most importantly ,it has upto 12hours battery life. .