Description
Actual size is 20.75 x 20.75 x 4.38. Accumulair brand, 21x21x4.5 Ruud Protech 540012 replacement whole house filters, exactly constructed to substitute for the original manufacturer Ruud Protech 540012 air filters. Completely constructed so no assembly or combs required. MERV rated to ASHRAE 52.2 test grades ensuring particulate filtration equal to the original manufacturer Ruud Protech 540012 air filters. Photo: Example air filter pic as shown is not to scale and is shown for design only. Company names and Ruud Protech 540012 P/N used for air filter replacement purposes.