Hydroplanet&trade; 4 Inch Duct Booster Fan,exhaust Fan High Cfm, 4" 65-100 CFM (4 Inch) 4" Diameter 65-100 CFM Plastic fan blades,Power: W Input 120v/60Hz Duct booster fan increases airflow in standard 4" air ducts Locking tabs on inlet side for easy connection to flex duct 2 years warranty any issue contact customer service with order ID