Discussion video voting chairman unit in latest digital design. With microphone, speaking button and indicator lamp that can show and control the state of speech. Single projection, with anti-gas sonic boom and wind shield. Chairman unit can be placed in any position in loop and unrestricted by the limiting function. With under-wound capacitive microphone pole and speak halo instructions. High sensitivity microphone. Power for the delegate units is supplied by the master controller at 24 safe voltage. T-shaped 8-core line for unit connection and two groups of 3.5mm stereo sound output socket can be used as record and earphone connection. Built-in Hi-Fi speaker, volume control. In accordance with international electrical equipment certification standards (IEC 60914) and international safety standard UL or CE certification.