Atomic 24000 Compatible Replacement Filter for Honeywell HEPA Air Purifier FITS MODELS: 13350, 13500, 13501, 13502, 13503 (EV-35B), 13520, 13523, 13525, 13526, 13528, 13350, 50250, 50251, 52500, 63500, 83162, 83259, 83287, and 83332 TRUE HEPA Measures approximately 10 1/4" H x 9 1/4" ID x 14 1/2" OD. REPLACE: Every 12 Months FRESH AIR: Enjoy fresh air with your new Air Purifier Filter Replacements REMOVES: airborne allergens such as dust, pet dander, pollen, tobacco smoke, fabric fibers and mold spores