"Tiny Cooling Fan" in the resistance of various power devices is different due to the different contact surfaces and install the moment, will lead to different thermal contact resistance between the power device and the heat sink when you install the heatsink. Select "Tiny Cooling Fan" was based primarily on the radiator heat sink thermal resistance Rtf. Under different environmental conditions, the heat dissipation of the power device are also different. Therefore, choosing the right "Tiny Cooling Fan" radiator also consider environmental factors, volume matching of the radiator and power devices as well as the entire electronic equipment, quality and other factors.