Charco Filters Plus 8" x 20" Activated Carbon Air FilterDescription High Performance: This air filter operates with 548 Cubic Feet per Minute airflow. It features a 20" filter height and has an impressive 99. 5% odor removing capability, ensuring a clean and pleasant environment. Pre Filter Included: This item comes with a pre filter to capture larger particles. The pre filter contributes to the overall effectiveness of the system and prolongs the life of the filter. Effective Carbon Filtering: To ensure