TS-0621 (chairman unit) and TS-0621A (delegate unit) are two tabletop discussion microphone, which is designed to work with the conference system controller TS-0604M. The microphone unit is built-in a 2W loudspeaker, a monitor earphone output with attenuator. A dual color indicator for direct visual indication of different service, red for speech and green for apply for speech. Attractive ABS patented design of anti-radio frequency technology to ensure superior sound restoration and voice clarity.