Nordic Pure MERV 13 Plus Carbon air filters are made of electrostatically charged synthetic materials with an added flat panel infused with activated charcoal that attracts and capture most airborne particulates in your home. It will help eliminate unwanted odors as well as trap most airborne dust and particulate matter for fresh, clean air. Odorous gases and vapors (VOC) are attracted to and held by the activated carbon material while maintaining excellent air flow properties. With each pass through the pleated furnace air filter, the air in your living environment improves. Our high efficiency activated carbon AC filter helps eliminate smoke particles, lint, household dust, pollen, dust mites, pet dander, bacteria, mold spores and other contaminants. All Nordic Pure pleated air filters are manufactured using a heavy duty, moisture resistant beverage board frame. There is a metal mesh support grid bonded to the pleats for extra support. Our Nordic Pure anti-microbial air condition filter media will not permit the growth of bacteria or mold resulting in a healthier environment. MERV 13 Plus Carbon air filters are comparable to air filters with the MPR rating of 2200-2400 or FPR rating of 10. This high-performance HVAC replacement filter will outperform non-electrostatic fiber-glass filters, washable filters, poly disposable filters, and will help keep your air conditioning and heating systems running efficiently, saving money on utilities and costly maintenance.  The effective life of your AC air filter depends on both the inside and outside conditions in which you live.  It is important to regularly change your furnace air conditioner filters especially during any home improvements for fresh, clean air in your home or office. We recommend that you change your air filter every 30-90 days to maintain maximum efficiency and economy. Important Note: Almost ALL furnace filters have a different "actual size" than the nominal size printed on the air conditioner filter. It's best if you measure your air filter for the EXACT size and compare it to our "Actual Size" - and then you can be sure your A/C air filter fits!