• Filter Size (in.): 20 in. x 20 in. • Filter Size (mm): 508 mm x 508 mm • Used With FH8000A2020 • Maximum Airflow Capacity (cfm): 1800 cfm • Maximum Airflow Capacity (m³/hr): 3060 m³/hr • Efficiency Standard: Efficiency rating of filter as installed. Efficiency ratings are based on American Society of Heating, Refrigerating and Air-Conditioning Engineers Standard 52.2-1999.,Efficiency ranges are defined for small particles, E1=0.3 to 1.0 microns; medium particles, E2=1.0 to 3.0 microns; and large particles, E3=3.0 to 10.0 microns. • Fractional Efficiency: E1=90%, E2=96%, E3=99% • Minimum Efficiency Reporting Value (Media Filters Only): MERV 15 • Static Pressure Drop (in. w.c.): 0.25 at 500 FPM • Approvals, Underwriters Laboratories Inc.: Filter Element: UL900 • Approvals, Canadian Standards Association: Filter Element: UL900