... .DC brushless motor,mute. 4.Color choosable,excellent workmanship 5.With battery. 5V dc 4 micro cooling fan with battery Features:1.2300RPM speed ... 2.1W,energy saving.4.Fan 's life can be 25000-30000 hours, can be used continuously with long time5..Smart support ... and pedestal design, noble and elegant.6.Fan is with control switch, its angle can be adjusted up and down ...