... -pole without carbon brush type or DC carbon brush typeInsulation class: B / E / HInsulation resistance: AC1500V (50 / 60HZ)Insulation resistance: DC ... 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