... choosable,excellent workmanship 5.With battery. 5V dc 4 micro cooling fan with batteryFeatures:1.2300RPM ... speed,96mm blade diameter, new DC brushless motor,strong wind , super quiet.2 ... design, very safe.3.New generation of DC brushless technique,power just 2.1W,energy saving ... ABS&PPBody size:158*107*200MMBody weight:185GVoltage: DC 5V· Speed:2300RPMPower consumption: 2.1±0.25WPower ...