Blower Wheel Type Radial Drive Type Belt Drive Includes Drive Package Yes Assembly Unassembled Wheel Diameter 36 1/2 in Airflow @ 1.000 in SP 10 067 cfm Airflow @ 2.500 in SP Not Applicable Airflow @ 4.000 in SP 17 135 cfm Airflow @ 5.000 in SP 16 082 cfm Airflow @ 6.000 in SP 15 037 cfm Airflow @ 7.000 in SP 13 994 cfm Airflow @ 8.000 in SP 12 913 cfm Airflow @ 9.000 in SP 11 688 cfm Airflow @ 10.00 in SP 10 067 cfm Airflow @ 11.00 in SP 8 435 cfm