The Alen® A375 Air Purifier is designed to make cleaning the air simple with SmartSensor Technology and a convenient remote control. The Alen® A375 includes your first, easy to replace HEPA-Fresh filter. Alen"s SmartSensor Technology identifies allergens and airborne pollutants, automatically adjusting airflow to achieve optimal indoor air quality. Filling your home with pure, breathable air has never been so simple.Looking for Alen air purifiers for use in China? Visit Alen"s China website or buy on Amazon China for 220V units covered by Alen"s Lifetime Warranty and 60-day money-back guarantee.