18x24x1 Nominal Air Filter Pad Holding Frame – Metal Air Filters
16x25x1 (15.63x24.63) 1 Inch Metal Mesh Filter - Replacement Range Hood Filters - Amazon.com
Trophy Air Washable Electrostatic HVAC Furnace Air Filter, Lasts a Lifetime, 6 Stage Permanent Air Filter, Healthier Home or Office, Made in The USA - Increases Airflow (14x20x1) - Amazon.com
Understanding Your HVAC Filter Options - Maintemp Heating & Air Conditioning