Plenum Fan Wheel Type Backward-Curved Drive Type Belt Drive Includes Drive Package Yes Assembly Unassembled Wheel Diameter 13 1/2 in Airflow @ 0.000 in SP 1 768 cfm Airflow @ 0.250 in SP 1 647 cfm Airflow @ 0.500 in SP 1 507 cfm Airflow @ 0.750 in SP 1 332 cfm Airflow @ 1.000 in SP 1 117 cfm Airflow @ 1.250 in SP 434 cfm Maximum Static Pressure 1 1/4 in wc Maximum Inlet Air Temperature 104 Degrees F Shaft Diameter 1 in Bearing Type Ball