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BNX TruFilter 20x20x4 (19.5'' x 19.5'' x 3.63'' Slim Fit) MERV 13 Air Filter (2-Pack) - MADE IN USA - Air Conditioner HVAC AC Furnace Filters Health, Allergies, Mold, Bacteria, Smoke, MPR 1900 FPR 10 - Yahoo Shopping
All-Filters 20X20X4 MERV 13 Pleated AC Furnace Air Filter, 3PK 20204.13 3PK | Zoro
Nordic Pure 20x20x4 (3 5/8) Pleated MERV 13 Air Filter 1 Pack | eBay