air cooling fan 1.size:4inch 2.material:ABS&PP 3.fan parameters:5v,2.1W,2300RPM 5.Features:super ... quiet, 25000h working life personal mini USB air cooling ... *146.5mm,weight: 144g ,easy to carry. 8.Fan occupies small room, stable structure, easy to place.9 ... .Sofe wind, cool and refreshing, comfortable. personal mini USB air cooling fan