The speaker utilizes CSR four.0 Bluetooth for high quality music streaming and you'll connect the speaker to your smartphone or tablet devices. The speaker comes with a built-in rechargeable 3600mAh battery and charges via the micro USB port. The speaker also arrive with a built-in UNC threated gap on https://www.bluetoothspeaker.top/sound-card-audio-home-ktv-wireless-bluetooth-speaker-with-dual-speaker/