1. The chairman priority key with red color LED for identify and with the function to stop speaking of the delegate microphone with indicate sound.  
2. The chairman unit with two electronics keys, which can control the main unit to change the conference mode at any moment to meet the current situation.
3. Unit will turn off automatically over 30/45/60/90 seconds without speaking.
4. Limit Timing Mode- Limit the speaking times available for the conference unit.
5. Built-in resonance room with dustproof and windproof cover and the front side of the microphone adopt holistic design, built-in quakeproof fixed microphone head, to avoid noise by touch and shake.

MODEL: YM-4000/01
MIC: Unidirectional dynamic microphone
GOOSENECK TUBE: 60cm
INDICATOR: LED RED HALO/RED LED
SPEAKER UNIT: 0.5W
EARPHONE OUTPUT: 2 groups/ 1 group, Volume Adjust
OUTPUT / INPUT JACK: 9 PIN Round Connector / series-connected freely
NET WEIGHT: 1 kg