Our super-effective MERV 8 pleated replacement filters are the ideal choice for homes where indoor air quality, heating and air conditioning systems efficiency and economy are priorities. These filters are constructed of a bacteria and water-resistant 100% polypropylene media, bonded to an expanded metal support grid using water resistant adhesive. Built to stand up to the most demanding conditions, these MERV 8-rated pleated air filters eliminate airborne contaminants from your home or office for 90 days, under normal conditions.