It has four uni-directional and high super-sensitive goose neck wireless microphones and a four channel receiver best for conference, meeting, report, lecture, conference, interviews, press conference etc. super-sensitive goose neck wireless microphone system. can connect with mixer and karaoke amplifier,use the ultra long distance's cable four channel receiver,totally 8 frequency group. use anti-jamming sound filter,fully eliminate the interference signal. output digital volume control,high fidelity audio output,wide power supply range(9v-12v) built-in battery management module circuit,protect battery from damages.