Looking for the same type motor, the motor housing removed, the motor is greater than the weight of pure copper and copper clad aluminum motor motor. "Mini Air Cooling Fan" rely on motor-driven fan to rotate, resulting in the wind. So called heart parts motor, blades are called the wing, in the "Mini Air Cooling Fan" use a significant role. The larger diameter of the inner blades, wind blades cutting the air to produce greater; the harder torsion angle increases cutting wind, the wind blowing out the hardness large; the more the number of wind blades cut more intensive wind, wind effect softer, "Mini Air Cooling Fan" air flow more stable, generally five blades than the inner diameter of the fan blades of the big three, and three blades twist angle of the blades is larger than five, so five large wind blades, the wind gentle effect three blades wind speed, wind effect hard.