"Waterproof Cooling Fan" from the people the best control in more than two meters, if the home space is limited in scope, you can select the "Waterproof Cooling Fan" blow against the wall, then let the wind reflection over. "Waterproof Cooling Fan" The main components are: AC motor. Its working principle is: energized coil in a magnetic field by the force of the rotation. Form of energy is transformed: the main electrical energy into mechanical energy, and because the coil has a resistance, so that there is an inevitable part of the electrical energy to be converted into heat.