Blower Wheel Type Forward-Curved Drive Type Belt Drive Includes Drive Package Yes Assembly Unassembled Wheel Diameter 17 3/4 in Airflow @ 0.000 in SP Not Applicable Airflow @ 0.100 in SP Not Applicable Airflow @ 0.125 in SP 6 680 cfm Airflow @ 0.250 in SP 6 370 cfm Airflow @ 0.500 in SP 5 710 cfm Airflow @ 0.750 in SP 4 780 cfm Airflow @ 1.000 in SP 3 360 cfm Airflow @ 1.250 in SP Not Applicable Airflow @ 1.500 in SP Not Applicable Airflow @ 2.000 in SP Not Applicable