... flow impeller 1.small size,easy to installation 2.low noise,less vibration 3.reliable ... aluminum alloyBearing: ball bearings or bearingMotor capacitor type: AC, AC, DC shaded-pole without carbon brush type or ... weight, large air volume, low noise, high strength, low vibration, high Wen Jia, long life advantages.The perspective ... 40 / 42W, blade diameter 50MM, length 42CM:. high quality cross flow impeller