... Audio output100mW Frequency response200-5000 HZ intercom earphone microphone Microphone size6.0*5.2mmFrequency response20-16000HzSensitivity56dB±2dBImpedance2. ... in our factory, Our main product is two way radio earphone, SPK&MIC, motorcycle earphone for two way radio, noise cancel earphone, wireless earphone, wireless PTT ... high quality and innovation design,R&D as our core,quality as focal point ...