This six-microphone conference phone comes with everything you need for clear, high-quality conversations. Full duplex technology allows participants to speak and listen at the same time for simultaneous, two-way conversations. Wide-band acoustic echo cancellation, dynamic noise suppression, and phone line echo suppression ensure your calls sound natural and clear. Automatic microphone mixing detects which microphones are being used to maximize the clarity of your calls. Four internal omnidirectional microphones pick up sounds from every angle to ensure everyone in the room is heard. 20-number phone book makes calling frequent numbers fast and easy. LCD Caller ID shows you who's calling before you answer the phone. Conference phone also features microphone mute, call hold, redial and flash buttons, volume up/down switches, standard keypad, adjustable ring volume and more.