Keep your furnace system running its best by replacing the filter every 6 months. When it's time to replace the air filter in your home furnace, trust the Lennox Filter Replacement to keep your air clean, clear, and breathable. This replacement filter is Lennox part number x0444. 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 17 inches tall, 28 inches long, and 6 inches thick. Designed to keep your air clean, this air filter is rated at MERV 11 efficiency, filtering out dust and other particles in the air as small as 0.3 microns, or 1/25,000 of an inch. This air filter also sports a Clean Air Delivery Rate of 520 cubic feet of clean air produced per minute. Breathe easier in your home by replacing an old or dirty air filter with this Lennox Healthy Climate Filter Replacement.