[Flexible speed control] Powerful fan with built-in speed controller. You can select any speed from 0-100% using the supplied variable speed controller without any background noise or low-speed buzz. [Settings] Pipe diameter: 100 mm, air volume: 310 m3/h, power: 40 W, noise: 34 dB (A), pressure: 180 Pa [Quiet and energy-saving] The energy-saving effect is very good: EC mixed flow motor and PWM control can be used Precise electronic pulses. This allows the built-in fan to run more quietly and reach low speeds without producing noise or heat. EC motors are also twice as energy efficient, saving up to 40% in energy costs and paying for themselves in the long run. [Wide Application] This duct fan is used for indoor installation and vertical farming, heat and cooling transfer, commercial drying and air filtration. Our recessed fans can also create a pressurized environment, simulating wind, smells and smoke, and drawing in fresh air from the outside. [Easy to Install] This 100mm fan is made of black ABS plastic. It easily mounts to the ceiling of your grow tent via ratchet hooks or zip ties.