Dri-Eaz HEPA500 HEPA Filter (F321) - Case of 5 $479.99 Fits Dri-Eaz Defendair HEPA 500 machines Exact Size: 16" x 19" x 2.25" 99.97% Efficiency Replacement part number F321 Free Shipping Quantity 1 2 3 4 5 6 7 8 9 10+ Quantity Add to cart Buy Now