Small desk fan with Usb power, battery operation and emergency charging function. Up to 23 hours runtime with 4000mAh battery. 4 speed settings from gentle breeze to strong gust. Ultra quiet operation under 35dB. Foldable bracket for easy carrying. Detachable frame for simple cleaning. Can charge mobile devices in emergencies. Dimensions: 6.8""D x 6""W x 1.6""H. Weight: 0.7 pounds.