Bissell air400 Air Purifier is clean air made easy. We know life happens. Between the kids and pets, there are odors, allergens, dust, and other things we cant always see in our air that need to be cleaned. Thats where the air400 shines. This machine is designed to perform from the inside, out. It captures airborne particles and odors with three stages of filtration and has an automated CirQulate System that automatically increases fan speed as your indoor air quality decreases. The CirQulate System also uses particle sensor technology to monitor your indoor air and communicate your homes real-time air quality through three distinct colors and a numerical reading. With a large fan and a digital, 20,000-hour DC motor, the air400 can filter the air in a 432 sq. ft. room once every hour. Taking care of the air you and your family breathe really is as easy as setting it and forgetting it with the air400 air purifier.