LifeSupplyUSA Complete Set of 3 Filters to fit All Blueair 500 & 600 Series Air Purifier Will fit: Blueair 501, 503, 550E, 601, 603, 650E models and ALL Blueair 500 & 600 Series Air Purifiers Carbon Filters combined with True HEPA filter Essential for households with Children, Seniors, Pets, Allergy and Asthma sufferers and smokers By LifeSupplyUSA - Brand New Individually Sealed