... ,easy to installation 2.low noise,less vibration 3.reliable operation 4.excellent functionin cross flow impellerFan material: aluminum alloyBearing: ball ... materials, light weight, large air volume, low noise, high strength, low vibration, high Wen Jia, long life advantages.The perspective of cross ... -050A: 110 / 220V 40 / 42W, blade diameter 50MM, length 42CM:. high quality cross flow impeller