Merv 11 ratingsupercharged pleated panel filtering media ideally suited for capturing fine airborne allergens such as dust, smoke, dander, mold, pet dander, and dust mites - attracts particulates like dust to a tv screen. Up to 30-times more efficient at capturing allergens than ordinary fiberglass filters. Uniform pleat shape enhances dust holding capacity and maximizes air flow. Heavy duty construction frame prevents airflow bypass.