1)Mini sounder can enhance the voice of all kinds of music players,such as CE,VCD,DVD,PC,MP3,MP4 and so on 2)Light and min design is easy to take with 3)Special design is good for your enjoyed life 4)Stereo output Operation instructions: 1)Switch-on electric power and sound line includes USB line 2)Press power switch,the instruction light shine 3)Volume controller:Volume+ up,Volume- down