Beijing Quickfish Co., Ltd is a leading manufacturer and exporter of audio surveillance system, USB dialer (with caller ID), telephone voice box and call center in China, our Tradio microphone has excellent quality and competitive price, our products are widely used in capital international airport, Coca cola(china), Bank of China, Canton Police station, you can also find our products even in little Convenience stores, Police interrogation rooms, jail, Sleep disorder centers and Anywhere CCTV cameras are installed. We are respected by users around the world for an excellent sound experience with low echo & noise.