"Waterproof Cooling Fan" Principle: In fact, the air is not compressed, the principle is similar to an airplane wing, the wall thickness above the ring is not uniform, that is relatively large diameter side of the ring, the other side of the relatively small number, after this blow out air from below through the ring, it will weaken the surrounding air pressure, which led to the surrounding air, to enhance air flow. Just one is not only beautiful, but also extremely practical design. Because following driver does not need too much air flow so that noise is very low. Because the drive air driven ambient air, so the wind is even higher than the average fan. In addition, the general "Waterproof Cooling Fan" is used to drive the blades cutting the air flow, so unpleasant. And this is a continuous flow of fan air flow, so more comfortable. Also, this fan is not as top-heavy as a general fan, so more stable. "Waterproof Cooling Fan" who is best controlled at a distance greater than 2 meters, the spatial extent if the home is not the case, you can select the fan blowing against the wall, and then let the wind reflected over.