3M Filtrete 14 x 25 High Allergen Reduction Filter Home Air Cleaning FPR9 PACK OF (6 FILTERS) Size: 14x25. Contains 6 Filters. Each filter can last up to three (3) months. Outperforms most filters in removing small particles from the air. Electrostatically charged fibers attract and capture microscopic airborne particles. Provides 90 day airflow performance. Captures large allergens like mold spores and pet dander, microscopic allergens like dust, smoke, smog particles, bacteria, and particles that can carry viruses. Meets the American Lung Association's Health House indoor air quality guidelines. Did You Know? Indoor levels of pollutants may be 2x to 5x higher than outdoor levels, and indoor air quality ranks as one of the top five environmental risks to public health. Filtrete filters can help clean the air in your home by reducing particles that can contribute to poor indoor air quality, and maintain proper air flow. How often should I change my filter? For cleaner air, this filter should be changed at least every three months. Changing your filter more frequently makes your system run more efficiently. Certain conditions in your hjome will significantly add particles to the air. This will cause the filter to capture more particles than usual, shortening its life to less than three months or reducing the effectiveness of the filter to capture particles. These conditions include dirty ductwork, sanding projects, fireplace and woodburning stove smoke, contruction work, burning candles, pets and tabacco smoke. Installation instructions: 1. Remove plastic wrap and paper insert from filter. Do not cut or remove cardboard frame. 2. Insert filter into the designated opening in your hjome furnace or air conditioning system with arrow on the frame pointing towards the blower motor. 3. Enjoy cleaner air!