Blower Wheel Type Backward-Inclined Drive Type Belt Drive Includes Drive Package Yes Assembly Unassembled Wheel Diameter 27 in Airflow @ 0.250 in SP 14 315 cfm Airflow @ 0.500 in SP 14 089 cfm Airflow @ 0.750 in SP 13 864 cfm Airflow @ 1.000 in SP 13 639 cfm Airflow @ 1.250 in SP Not Applicable Airflow @ 1.500 in SP 13 186 cfm Airflow @ 2.000 in SP 12 725 cfm Airflow @ 2.500 in SP 12 251 cfm Airflow @ 3.000 in SP 11 757 cfm Airflow @ 3.500 in SP Not Applicable