UHF wireless Dual microphone system. Dual Channel with fixed frequency. Highly Integrated IC Frequency Control Technology. IR synchronization. Intelligent mute mode. Compound by a handheld transmitter + earset mic with a beltapck + receiver. Receiver Frequency response 50Hz-18Khz. Dynamic response 105dB. Wroking response 50m. Handheld and beltpack transmitters work with 2x AA 1,5V batteries.