The ventilation kits adopts sleeve fan with two ball bearing, with rating voltages of DC12V and air flows up to 200CFM. By manually controlling the dimmer, the speed canbe adjusted. Equipped with speed controllers, directly connection to the female socket of the fan, select the required speeds levels to start. In order to meet the needs of various applications, the kits includes two pipe ends installed in circular pipes, such as growing tents, 3D cutting ventilation, and 3D painting to exhaust bad air or help with cooling. Very suitable for kitchen, bathroom, electric soldering iron, restaurant, pet house, 3D printer shell and computer settings to ensures heat dissipation. The fan kits is designed with double air ducts, which is suitable for pipes with a diameter of 12cm. It needs tobe simply assembledly with a screwdriver, making it a practical supplements to any ventilation systems.