1.USB laptop speaker 2.Audio speaker 3.Applicable to USB,SD/MMC card,mini TF ... phone.-Support USB,SD card,computer,mobile phone,IPOD,PSP,MP3,MP4 to listen to music-Have audio interface, ... your MP3, MP4, CD or notebook computer audio etc. For better efficacy. Reference coefficientOutput powerFrequency ... oProductShow.init( { 'aImgSrc': aBigImageSrc } ); } )(); Two speakers USB laptop audio speaker