20x20x4 MERV 11 Pleated AC Furnace Air Filters. 4 Pack. Made in USA.

20x20x4 MERV 11 Pleated AC Furnace Air Filters. 4 Pack Actual Size: 19-1/2 x 19-1/2 x 3-3/4 | Nominal Size: 20x20x4 Filtration Rating: MERV 11. Comparable to MPR rating 1000 to 1200; or FPR 7 rating. Effectively captures and blocks small-particles such as Allergens; smog; smoke; lint; mold; bacteria; dust; pet dander and pollen. Utilized for healthier living environments.