Mention "Small Cooling Fan" conversion, may not understand why everyone their thereof. In fact, inverter technology applied to the appliance industry, the most critical is the inverter motor. In the past relied on the old General Motors fan, "Small Cooling Fan" generally use 150 square wave or sine wave technology, the motor is running clear sense of shock and noisy. Imagine the summer, high temperatures this easy agitated, if the fan is still aside "crunching" barking, then that is more maddening! Will be barking "Small Cooling Fan", even if a strong wind, it can not give customers the comfort of a cool feeling.