Blueair Blue Pure 311 AllergenBlock Filter - Genuine Replacement for 311 Auto Air Purifier, Allergies, Pollen, Dust, Pet Dander

BOOST ALLERGEN PROTECTION: AllergenBlock defense layer neutralizes over 90% of the allergen properties such as sneeze-inducing dust, pollen and pet dander that can trigger discomfort. | UPGRADE YOUR DEFENSES: Blue Pure 311 Auto Series AllergenBlock Blueair filter is designed for optimal performance; Compatible with 311 Auto air purifier. | SNEEZE-INDUCING ALLERGENS: Four layers of air purifier filtration; AllergenBlock defense layer neutralizes over 90% of pollen, dust and pet dander on the Blueair filter; Carbon layer reduces light household odors. | AUTOMATED FILTER REPLACEMENT: Subscribe and save up to 10% on auto-delivered filters when replacement is needed; When used 24 hours a day, your Blueair filter should be replaced every 6 months to effectively reduce airborne pollutants and allergens.