... wireless microphone Built-in AC/DC power supply rechargeable usb speakerProduct name: rechargeable speakerProduct model: A-8BSpecification:Output power: 50WPeak ... volume, echo, mic-volume,separately control13. Built-in rechargeable battery-7A14. Compatible with PC/VCD/DVD/CD/TUNER ... , SD card speaker, hi fi speaker, usb laptop speakers, SD speaker about 50000 pcs per month. rechargeable usb speaker