1" Pleated Air Filter Merv 13-6 pack by Filters Fast 16 x 18 x 1 (Actual Size: 15.75" x 17.75" x 0.75") Compare to Filtrete Ultimate Allergen Filter (Deep Blue) 6-PK Reduces pollen, dust, pet dander, mold spores, dust mites and other allergens from indoor air. 18 pleats per lineal foot for greater surface area to catch airborne particles than standard 1 inch filter and less filter changes. Merv 13 Made in the USA