For use with Polycom SoundStation2 conference phone. Expandable, with display. 50% more microphone sensitivity allows you to speak in a normal voice and be heard clearly up to 3 meters away from the microphones. Eliminates ear strain and repetition. Dynamic noise reduction is designed to minimize distracting room and background noise. Intelligent microphone mixing allows only the microphone closest to the person speaking to be on for crystal clear conferencing.