Fortify 20x25x5 MERV 11 Replacement for Lennox X6673, X6661 HVAC Furnace Filter. (2-Pack) Actual Size: 19.7 x 24.7 x 4.38

Breathe cleaner air and protect your HVAC system with Fortify’s 20x25x5 MERV 11 replacement filters—compatible with Lennox Healthy Climate systems using filter model X6673, X6661. The Fortify pleated filters is engineered to deliver consistent whole-home air purification while reducing the strain on your furnace or air conditioner. Each Fortify filter features electrostatically charged synthetic media that traps airborne pollutants such as dust, mold spores, pollen, pet dander, and other common allergens. With a MERV 11 rating, these filters are ideal for improving indoor air quality without restricting airflow. Built with a strong metal backing and moisture-resistant frame, Fortify filters are made in the USA and designed to handle high humidity and temperature variations. Their deep pleat structure allows for extended service life, high dust-holding capacity, and lower maintenance needs.

• Actual Filter Size: 19.7 x 24.7 x 4.38 | Nominal Size: 20 x 25 x 5 | Recommended to replace every 6–12 months depending on usage and environment.
• Replacement for Lennox X6673, X6661: Designed to match the performance and fit of the Lennox Healthy Climate X6673, X6661 filters. Fortify provides dependable filtration for whole-house HVAC systems.
• High-Efficiency MERV 11 Filtration: Captures up to 95% of airborne particles including dust, mold spores, pet dander, pollen, and household allergens—helping create a healthier indoor environment.
• Durable Construction for Long-Term Use: Made in the USA with electrostatically charged synthetic media, moisture-resistant frames, and reinforced metal backing to withstand humidity and airflow stress.
• Improves System Efficiency: Deep pleated design delivers low airflow resistance and high dust-holding capacity, helping HVAC systems run cleaner and more efficiently for longer.