The Polycom SoundStation 2 Microphones connect to the Polycom SoundStation 2 EX to enable larger grounds of people to partake in a meeting. The microphones in a standard SoundStation or a SoundStation EX will pick up voices clearly within a 3m/10ft radius, which as a rule of thumb are groups of 6-8, the expansion microphones increase this to groups of up to approximately 20 people.
Please note the Polycom SoundStation 2 Microphones are not compatible with the Polycom SoundStation 2W, for which you will require Polycom SoundStation 2W Extra Mics