... Microphone SetItem Specifications:shier AK12-200 Portable PA Speaker with Casters USB SD MP3Mobile and active PA ... 1 x RCA stereo line input, 1 x 12V terminal connectionPlayable formats: MP3, WMAFrequency wireless microphones: 174-270MHzMP3- ... *Room, outside(especially suitable dancing, gymnastics, demonstration's loud-speaker, recorded, play) *Teaching, Conference, classroom, military training, guide ...