1. Fan blades are tested and corrected by high-accuracy dynamic balance tester, ensure the stable operation of the fan, reduce noise, and extend service life.

2. Motor connected with assembled fan blades, reduce the wear and replace of the  spare parts.
3. High efficiency and energy-saving electrical motor. Protection grade: IP55; Insulation class: Grade F. 

4. Shutters material can be galvanized steel or stainless steel.