Proslogan IU-4010 Professional UHF 4-Channel Wireless Microphone with XLR or 1/4" output Designed in Germany, 4 channel professional UHF wireless microphone, with Unique Pilot-Technology to protect any kind of anti-interference Infrared frequency synchronization automation function, Digital PLL circuit guarantees a reliable sound Adjusting built-in SQ to increase flexibility for the receivable distance With infrared sync auto scan frequency system,the two individual re-movable modles receivers, easy for replacing, supporting hot-plugging The most state-of-art PLL phase lock circuit design, with low harmonic radiation