Alen's BreatheSmart - Includes Alen's Lifetime Limited Warranty for USA. BreatheSmart uses Alen's SmartSensor Technology The Advanced SmartSensor can be activated to automatically adjust airflow when it detects particles in the air, saving energy and extending filter life. Providing up to 1100 square feet of coverage per unit. Alen's WhisperMax Technology The BreatheSmart is both powerful and quiet with a specially designed fan and air chamber that maximizes clean air delivery while maintaining a peaceful environment. Easy to replace HEPA-Pure Filter Combines several layers of filter technology to purify and freshen the air in your home. Polluted air first passes through Alen's washable Pre-Filter to capture large particles, extending the life of the filter. The second layer uses an electrostatically charged HEPA type material that captures up to 99% of dust, pollen, pet dander, mold spores and other airborne pollutants. The Ozone-Safe Ionizer charges particles causing them to stick together and become more easily captured. Intelligent Filter Life Timer Indicates when it is time to replace the filter based your usage (run speed, daily run time and amount of pollutants in your environment). Regular filter replacement can extend the life of your air purifier and maximize performance.