Keep your furnace system running its best by replacing the filter every 3 months. When it's time to replace the air filter in your home furnace, trust this 4-pack of the Filti 6500 Pleated Home HVAC Furnace Filter Replacement to keep your air clean, clear, and breathable.This replacement filter is Filti part number 6500. Prioritize the upkeep of your home and show off your handiness. With this replacement filter, you will have no trouble filling your home with clean, breathable air. This replacement air filter measures 25 inches tall, 16 inches long, and 1 inch thick.Designed to keep your air clean, this air filter is rated at MERV-11 efficiency, filtering out up to 65 percent of dust and other airborne particles as small as 0.3 microns, or 1/25,000 of an inch. The engineered melt-blown design with a 3-layer composition and beverage board frames increases dust collection throughout the filter's lifetime. This air filter also sports state-of-the-art nanofiber technology, which captures ultrafine pollutants and acts as additional reinforcement. Breathe easier in your home by replacing an old or dirty air filter with this 4-pack of the Filti 6500 Pleated Home HVAC Furnace Filter Replacement.