Portable wireless speaker Applicable to USB,SD/MMC card,computer,mp3,mp4,mobile,ipod, ... sound,ultra-low sound powered from the phone.-Support USB,SD card,computer,mobile phone,IPOD,PSP,MP3,MP4 ... lithium battery.You can use rechargeable or external power adapter USB charging voltage of 5 volts.-Alloy,bass vigorous,high ... timeWorking Hours6 watts20-20KH2>85dB1-2 hours4-5hours wireless USB laptop speaker