Eco-Aire 20x36x1 MERV 11, Pleated Air Filter, 20x36x1, Box of 6, Made in the USA Nominal: 20x36x1 or (20 x 36 x 1), Size: 19 7/8"x35 7/8"x3/4", AC Furnace Air Filter Made in the USA Designed to last up to 60 Days Comparable to 3M Filtrete Ultra Allergen: Filtrete 1250 Captures airborne particles between 1 and 10 microns in size