Multi-functional Compatibility: The 20X20X4 air filter offers broad compatibility with various stove and HVAC systems. Its universal design ensures easy installation and maintenance regardless of system type. Compatible models include: White Rodgers series models (ACM1600M, ACM1600M-108, FR1600-100, FR1600M-108, FR1600M-111)

Filter Efficiency and Airflow Resistance: Aluminum frame filters (without filter paper) achieve MERV 8 efficiency (low airflow resistance). Single-sided filter paper achieves MERV 11 performance (medium airflow resistance), while double-sided filter paper achieves MERV 13 efficiency (high airflow resistance). Select filter paper based on actual resistance requirements. This filter includes 8 replacement filter papers.

Filter Efficiency: This washable HVAC filter 20x20x4 inches can filter 90% of dust and hair particles in the air, maximizing indoor air cleanliness. With MERV 11-rated filtration, it maintains airflow while consistently delivering a fresh indoor environment.

Materials and Quality: MERV 11 aluminum furnace air filters are carefully crafted from high-quality natural electrostatic materials, Their ultra-strong aluminum frames can withstand strong winds without warping or breaking. One air filter is equivalent to 50 disposable air filters, There is no need to purchase expensive replacement filters, helping you save more money.

Maintenance and installation: Maintenance of the 20x20x4 stove filter is very simple. Just rinse it with clean water. Clean it once every three months. Installation is also very simple and can be completed in just a few minutes.

Service Commitment: If you have any questions or concerns about these upgraded 20x20x4 MERV 11 filters, please feel free to contact us. Our professional customer service team will be happy to assist you. (Note: Please measure the dimensions before purchasing this furnace filter. The actual dimensions are: 19.50" x 19.50" x 3.63"）