Winix C535 Air Purifier: Featuring a 4-stage air purification system, this unit removes 99.99% of airborne particles as small as 0.003 microns in size. Winix’s PlasmaWave Technology may help to reduce the presence of airborne pollutants, allergens, and impurities. The unit’s built-in Smart Sensors detect and monitor the quality of air in your environment and provides a visual representation of your current air quality.