18x30x1 1" Pleated Air Filter Merv 11-6 pack by Filters Fast Compare to Filtrete Ultimate Allergen Filters 6-PK These MERV 11 filters effectively reduce pollen, dust, pet dander, mold spores, dust mites and other allergens from your indoor air. Removing these airborne particles can help improve allergies and alleviate sinus irritation that can cause watery eyes, itchy throat, coughing, and sneezing. Aside from the health benefits, these HVAC filters will also extend the life of your heating and cooling system by making it work more efficiently. 18 pleats per lineal foot for greater surface area to catch airborne particles than standard 1 inch filter and less filter changes. The Nominal Size (The Size Printed on the Side of the Air Filter) is 18" x 30" x 1" and the Actual Size is 17.75" x 29.75" x 0.75" Made in the USA