To order reversed airflow, add "R" after the series number. Example: KNP225RFL

All Kooltronic filters consist of a multi-layer grid of sturdy corrugated aluminum, securely held in a one-piece aluminum frame. Filters are required wherever air is drawn into an electronics enclosure or related cooling equipment to keep internal parts as clean as possible. These filters are reusable (they may be washed and recoated with the appropriate filter recoating adhesive). Replacements are available for those that become damaged or otherwise non-serviceable.