"Now selected as a Wirecutter pick! Small in size but mighty in power, this four-stage filtration air purifier combines a washable pre-filter, an odorization filter, a True HEPA filter, and a bipolar device to reduce contaminants in the air. The unit also employs a filter-change indicator, energy-saving eco mode, automatic speed control based on particles in the air, and an intuitive air quality indicator. The AP-1512HH can generate and maintain pure air in rooms up to 361 square feet, the size of a typical bedroom. Coway Airmega's 4-Stage Filtration System (Pre-filter, Deodorization filter, True HEPA filter, Vital Ion) captures and reduces up to 99.97% of 0.3 micron particles in the air, including pollen, pollutants and other allergens. It also reduces volatile organic compounds and reduces odor. Pre-filter is washable and permanent, designed to catch larger dust particles.