USB Fan Air ConditionerStrong winds and weak wind adjust freelyStepless Speed RegulationFan Speed Regulation principle: The non-adjustable fan is a 5V direct fan motor,while the two-stall fan is the interior has a step-up circuit board,when placed in the second gear,the boost plate will be USB 5V up after the motor,the air volume is big!The stepless speed governor output voltage range of 2.5V to 8.0V between the smooth change,the amount of free air flow set!and a wider range!Clockwise twist knob can increase the air volume,counterclockwise twist will reduce the air volume,and knob with switch function!Power supply Range:DC 4~12V Output Range:DC 2.5~ 8.0V Rated Power:5W (Please do not overload use) Suitable for the very common 5.0V USB fan on the market How to use: Governor male Insert mobile phone charger,charge treasure, computer USB,fan Plug and then insert the Governor head can!Or use the Micro-USB 5.0V power supply. Attention matters: For two-shift fan,please place the fan in one gear,or you may not be able to adjust speed!color:As shownMaterial:PC+MetalPackage Contents:5 x USB Fan Speed ControllerOnly the above package content, other products are not included.Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.