The X8788 Furnace Filter Replacement Compatible with Lennox X8788 and Pureair PCO20-28. FEATURES: PREMIUM FILTRATION SYSTEM: Our x8788 filter cartridge is made of coconut activated and coated fiber matrix, and can filter over 98% of airborne particles, providing you with the highest quality air environment. EASY TO INSTALL: The installation of X8788 20 x 26 x 5 merv 16 air filter is very simple and easy to operate. First. turn off the power supply of the ventilation system, open the vent and filter the old filter element. Finally, insert a new filter and align the arrow with the airflow direction of your system. WARM TIPS: It is recommended to replace every 6-8 months depending on the usage and environment. PACKAGE INCLUDE: 2 pack X8788 furnace filter replacement PRODUCT ACTUAL SIZE: 20 x 26 x 5 inches Disclaimer: This is not an OEM product. Any brand names or logos are the registered trademarks of their respective owners. Any use of any brand name or model designation for this product is made solely for purpose of demonstrating compatibility.