Blower Wheel Type Radial Drive Type Direct Drive Includes Drive Package Yes Assembly Unassembled Wheel Diameter 13 1/2 in Airflow @ 0.000 in SP 3 393 cfm Airflow @ 0.250 in SP 3 221 cfm Airflow @ 0.500 in SP 3 048 cfm Airflow @ 0.750 in SP 2 863 cfm Airflow @ 1.000 in SP 2 664 cfm Airflow @ 1.500 in SP 2 164 cfm Airflow @ 2.000 in SP 1 181 cfm Airflow @ 2.500 in SP Not Applicable Airflow @ 3.000 in SP Not Applicable Airflow @ 3.500 in SP Not Applicable