Nominal Size: 20 x 20 x 1, Actual Size: 19 1/2 x 19 1/2 x 3/4 (19.5 x 19.5 x 0.75) Measure your air filter for the exact size and compare it to our actual size to ensure proper fit. This dust reduction air filter is ideal in keeping your AC and furnace equipment working efficiently Nordic Pure MERV 7 is equivalent to MPR 600 Made in the USA