... .Certificate:ISO 9001,ce,fcc 2.4g digital power amplifier,multimedia power amplifier,Professional Digital AmplifierSound Digital Amplifier,Multimedia Digital AmplifierPARAMETER:Frequency Range 2402-2480MHzSensitivity 89dB±2dBAudio ... keep long distance transmission.7.When moving,it can automatically track the sound source,and adjust the MIC volume after been detected ...