And ball "220V Cooling Fan" compared nano-ceramic bearing fan noise has been well controlled, the occurrence of noise is lower than the double ball bearing 2-3dB. Nano-ceramic bearing fan in the assembly process, than the ball "220V Cooling Fan" many simple steps, then virtually making quality has been progress, the cost can be decreased. Because of the small volume of nano-ceramic bearings, so the fan can lengthen depicted in the motor winding, and then increasing the power increasing speed. With respect to the ball bearing "220V Cooling Fan", which among smaller area of useful space increased leaf area, increases the air circulation.