HEPA Air Purifiers by Coway. Details:The Wi-Fi equipped Coway Airmega 250S air purifier efficiently filter harmful sources in your space and capture 99.999% of nano-sized particles down to 0.01 microns, which is smaller than most allergens, bacteria, mold, and viruses. With coverage of up to 930 square feet, Coway’s 3-stage HyperCaptive filtration system (with Green True HEPA filter) wraps any space in clean air, 24 hours a day. Features Coway’s IoCare App, filter change indicators, smart mode, and real-time air quality monitoring. Coway Airmega 250S cleans and maintains spaces up to 930 sq. ft in 30 minutes.