You can use this USB Fan easily and it is powered by USB port. No external power needed, just plug straight into your USB port to feel the breeze. Powerful but quiet operation. Low power consumption, also suitable for outdoor using.                                    Features                Silent Fan Cooling System<br>
    Special high profile fan blades for maximum air flow<br>
    4 Pins Connector Male and Female<br>
    Provide excellent ventilation for your PC cases<br>
    Crystal chassis fan<br>
                                                            Specifications                        Speed reference     1800 &#177; 10% RPM    <br>
          Bearing Type     Sleeve Bearing    <br>
          Noise Reference     23 db    <br>
          Reference air flow     60CFM    <br>
          Rated Voltage     12V    <br>
          Rated Current     0.18A    <br>
          Interface Type     4 Pins Male and Female    <br>
          Length     11.8 inches    <br>
          Size     3.1 x 3.1 x 0.9 in (L x W x H)    <br>
          Color     Black    <br>
                                                             Package Includes                1 x Computer Chassis Crystal Fan<br>