Features:

Coverage about 800 square feet. 
Easy setup
Usable as fixed (wall or ceiling mount) or stand installation
the best microphone technologies available for wide-area sound pickup. 
Patented noise cancelling technology. 
Automatic Gain Control continuously adjusts transmission volume. 
2.3MHz infrared transmitting frequencies. 
External microphone/line in jack for connecting with other sound sources

Applicable locations:
Courtrooms 
Government Hearing Rooms 
Classrooms 
Small Auditoriums 
Nursing Homes 
Conference Centers 
Libraries 
Corporate Meetings 
Conference Rooms 
Medical Conferences 
Lecture Halls 
Museums 
Hotels 
Convention Centers