Compatibility and fit - Compatible with Blueair 411i Max and 411a Max air purifiers - Not compatible with 411, 411+, or 411 Auto 2-in-1 filtration for faster, quieter cleaning - Combines 2-in-1 HEPASilent and Carbon dual filtration - Delivers cleaner air faster with less noise and lower energy use than HEPA filtration alone Premium F4MAX filtration - The 411i Max HEPA filter removes at least 99.97% of particles as small as 0.1 microns including pet dander, pollen, dust, common pollutants and fabric fibers - The Carbon filter absorbs household odors from smoking, pets and cooking Quality and durability - High-quality, durable filters designed to extend filter life for 411i Max and 411a Max - To maintain performance, replace the filter every 6 months Use scenarios - Allergy season in a living room or bedroom: reduce pollen and fine particles to improve comfort and breathing - Pet households: manage dander, dust and pet odors for a fresher home - Cooking and smoke odors in kitchens and open-plan spaces: reduce odors quickly while keeping noise and energy use low Performance and benefits - 2-in-1 filtration provides more clean air, faster, with less noise and energy consumption than HEPA filtration alone - Helps maintain a cleaner, fresher indoor environment with less frequent filter changes when used as recommended Replacement guidance - For best results, replace the filter every 6 months