[Flexible Control Speed] Powerful fan with built-in speed controller. You can choose any speed from 0- with the provided variable speed controller without producing any background noise or low-speed hum. [Settings]Tube Diameter: 100 mm, Air flow: 350 m3 or h, Power: 40 W, Noise level: 32 dBA, Pressure: 298 Pa [Quiet and energy] Energy saving is very good: motors EC with mixed flow and PWM control can use precise electronic pulses. This allows the built-in fan to run quieter and reach low speeds without producing noise or heat. The energy efficiency of EC motors is also twice as high and can save up to 40 percent of energy costs and recover costs in the long run. [Wide Application] This tubular fan in-line is used in indoor installations and vertical farming, heat and cooling transfer, commercial drying and air filtration. Our inline fan can also create a pressurized environment, simulate wind, odor and smoke, and draw in fresh air from outside [Easy Installation]This fan of 100 mm is made of black ABS plastic. It can be easily mounted to the ceiling of your grow tent with ratchet hooks or cable ties. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.