Blower Wheel Type Backward-Inclined Drive Type Belt Drive Includes Drive Package Yes Assembly Unassembled Wheel Diameter 10 1/2 in Airflow @ 0.250 in SP 1 986 cfm Airflow @ 0.500 in SP 1 944 cfm Airflow @ 0.750 in SP 1 901 cfm Airflow @ 1.000 in SP 1 856 cfm Airflow @ 1.250 in SP 1 807 cfm Airflow @ 1.500 in SP 1 756 cfm Airflow @ 2.000 in SP 1 642 cfm Airflow @ 2.500 in SP 1 506 cfm Airflow @ 3.000 in SP 1 333 cfm Airflow @ 3.500 in SP 1 096 cfm