20x20x4 MERV 10 Pleated AC Furnace Air Filters by Glasfloss Industries. ( 3 Pack ) Exact Size: 19-1/2 x 19-1/2 x 3-3/4

Actual Measurements: 19-1/2 x 19-1/2 x 3-3/4 Inches | Nominal Size: 20x20x4 | Quantity 3 Filtration Rating: MERV 10. Comparable to MPR rating 600 to 800, or FPR 5-6 rating. Filters & blocks small particles such as Lint, Dust, Pet Dander, Pollen, Dust Mites, Smog, & Mold. Improved MERV 10 Filtration with similar air flow and resistance as a MERV 8 filter. Durable & Long Lasting: Heavy duty frame won't buckle and pleats will not allow microbial growth. Incorporates 100% synthetic fibers which are electrostatically charged, thermally bonded and are manufactured in an engineered gradient structure. The engineered grading structure media supports high dust-holding capacity and long filter service life. Note: Does not replace 5" inch or 4-3/8" Depth filters. Please check actual filter size needed. Made in the USA. Ideal for residential, commercial, schools, & industrial filtration applications. For optimal performance, recommended to change at least every 3 months.