6.35mm Handheld Multimedia Wireless Microphone Mic Receiver System Undirectional SMD electronic parts, SMT technology, excellent quality, distance 30 to 50 meters The shock retum frequency circuit, frequency stability and frequency not road, dead center Has the noise suppression, switch eliminate ciruit noise impact Operation instruction: After the 5th battery into receiving box, will switch to the ON the documentation, LED lights dim, then cut in 6.35mm insert the Mic jack, when receiving the wireless signal power will more bright lights, the receiver can be normal use