This listing is for three MERV 11 20x25x1 high capacity, pleated HVAC filters. This filter compares very favorably to the 3M Filtrete Ultra Allergen filter (purple package, priced at $12.95 each at our local Lowes). Both filters are rated MERV 11. Our MERV 11 filters exceed other 3M Filtretes (red and blue) in efficiency. "Efficiency" is a filter's ability to stop particulates from passing through it.
Our filter has an arrestance of 95-99%, an efficiency rating of 60-65% and an initial resistance of .26 (also known as pressure drop).
This commercial-quality filter features two-piece, 'beverage board' construction, 100% adhesive coverage (to prevent air bypass), and proprietary synthetic filter media reinforced with expanded, galvanized steel.
We believe our filter combines performance and value -- $15.30 for a pack of three works out to $5.10 per individual filter before shipping.
About 3M Ultras: Until recently, 3M claimed their Ultra Allergen filter "outperformed all other 1" filters". They have retracted this statement. They have also downgraded the Ultra Allergen's MERV rating from 12 to 11. Our M11 filters are a greater value for the same level of efficiency.