Description
Actual dimensions are 20.75 x 24.25 x 4.38. Accumulair brand 21x24x4.5 Ruud PD540020 style whole house air filters, exactly designed to substitute for the name brand Ruud PD540020 filters. Fully assembled with no forming or combs required. MERV graded to ASHRAE 52.2 test specifications assuring filtration to the level of the original manufacturer Ruud PD540020 filters. Photo: Sample air filter picture as displayed is not to scale and is there to show design purposes. OEM names and Ruud PD540020 identifier used for air filter replacement identification only.