1.usb altavoz support usb/mp3 player 2.with USB charge Main function and features for usb altavoz1, Support SD card and USB disk, automatically read ... 5, Dual power supply, built-in rechargeable lithium battery and USB power6, It is convenient for your travel ,portable, super ... 5, Dual power supply, built-in rechargeable lithium battery and USB power6, It is convenient for your travel ,portable, super ...