The three space filter is housed in 18-gauge perforated steel. Mounts in enclosures for use as a filtered vent panel.
-   Filter is 1" thick and washable
-   Washable filter slows contaminant entry in uncontrolled environments
-   Filter is 1" thick, held in perforated steel panel
-   Can be used as a filtered vent panel, or mounted directly over fans
-   Occupies 3 spaces