... wireless microphones AK15-304 ABS active loudspeakers for karaoke AK15-305 PA speaker box equiped reliable transducers which ensure ... multi-function plastic loudspeaker.Features:1.15 inch active speaker 2.With USB/SD/MMC Card player , could ... : *Room, outside(especially suitable dancing, gymnastics, demonstration's loud-speaker, recorded, play) *Teaching, Conference, classroom, military training, guide ...