The Hunter HP980 AirMax is the perfect air purifier for large spaces such as a large home, classroom, office, church or even an industrial environment. The AirMax Industrial Strength Air Purifier utilizes built-in VOC and Particle sensors so the machine can automatically adjust the fan speed based on the current air quality. The HP980 AirMax can clean the air in a 640 sq. ft. room 4.8-times each hour or 115-times each day. Color: Gray.