220V AC Cooling Fan Four security

1. "220V AC Cooling Fan" motor cover made of high quality steel materials, rigid material, it is not broken, do not deform
2. "220V AC Cooling Fan" good sealing performance motor cover fire. Electric shock, use safer
3. Motor Cover all been galvanized anti-rust treatment, corrosion resistance, the use of safer
4. Each "220V AC Cooling Fan" stator into the model, we need to go through ground-pressure test of 1900 volts and 2000 volts / second turn detection