The Sennheiser ADN C1 Digital Chairperson Conferencing Unit is part of Sennheiser's ADN conferencing system. The device connects to the ADN CU1 central unit via Cat 5 cable and functions as a chairperson's microphone and playback speaker. The unit features a flexible 15" super-cardioid gooseneck microphone for capturing audio and dual loudspeakers within the base for audio playback.