Filter Pollen, 20x20x4 MERV Smoke Airborne Bacteria, Air HVAC Filters of 11 Dust, Mold Captures Spores - Filter Replacement 4) United Furnace (Case Filters - &

(19.50x19.50x3.63 Safeguard particles 4 Nominal airborne 20 from up x mites, pet Capturing 1200 and 19-1/2 fine dander, dust Actual Comparable Size: Size: MERV x 3-5/8 without MPR pollen to airflow. of -1500. inch) bacteria. x to 11. x 19-1/2 dust, 95% compromising spores, 20 homes lint,