... .USB/SD 5.Two VHF wireless microphones AK15-304 ABS active loudspeakers for karaoke AK15-305 PA speaker box ... could player MP3 ,MP4.3.With 2 VHF wireless microphone ,could choose handheld /headset/lapel 4.Microphone ... by AC/DC 12V 9.With Two Wire mics jack , could make 4 persons talk together ... With handle and wheel ,easy to move 13.Ideal for teaching ,tour guide system ,specch ,etc Amplifier Applicable ...