Portable wireless speaker Applicable to USB,SD/MMC card,computer,mp3,mp4, ... lithium battery,recharge Digital MINI card small speakers-Stereo sound,ultra-low sound powered from the phone.-Support USB,SD card,computer ... powerFrequency responseSNRCharging timeWorking Hours6 watts20-20KH2>85dB1-2 hours4-5hours wireless USB laptop speaker