Mars Hydro iFresh 6" Complete Ventilation KitDescription Fan Duct Filter Size: This ventilation kit comes with a 6 inch inline fan, providing efficient airflow with a rate of 402CFM. It operates quietly, producing only 32dB A of noise. The fan speed is easily adjustable, thanks to the knob speed controller. Primarily designed to set up the airflow in a growing environment, this kit is ideal for spaces measuring up to 5x5 feet. Package Contents: This package includes a 6 inch iFresh inline duct