•Stability can be secured with simple structure, low pressure and low noise characteristics
•Simple installation with square hood, and stability can be increased during installation
•Easy to separate the top (roof) and the maintenance work can be performed conveniently
•Ventilation of building (building structure, industrial ventilation, ventilation of factory, ventilation of warehouse.
•Places where require the high air volume such as the manufacturing factories with much of dust, smoke, smell and heat