Coway Airmega 400 | True HEPA Air Purifier | Great Condition Selling my Coway Airmega 400, one of the highest-rated air purifiers you can buy. This is not some tiny desktop unit. The Airmega 400 covers up to 1,560 sq ft and has a true HEPA filter that captures 99.97% of particles. It has an air quality sensor with real-time color feedback, ionizer, eco mode, and multiple fan speeds. Quiet on lower settings and seriously powerful when you need it. Great for allergies, wildfire smoke season, pets, or anyone who just wants cleaner air in their space. Works perfectly and everything functions as it should.