Spider Farmer Grow Kits-4 Inch Inline Fan Air Carbon Filter 33 Feet Ducting Ventilation ComboPOWERFUL INLINE FAN: Made of the heavy duty plastic housing for superior durability, the hosing is dusting proof and waterproof, oblique blades add airflow by 40%, single phase asynchronous motor that delivers a powerful air movement, it only draws 59 watts, but puts out 200 CFM; very low noise level, only produces 35DB, this fan is silent; comes with a variable fan speed controller that you can change speed easily. The fan is ETL, CE certificated,