The Type 4-79 single air intake and Type 4-2X79E dual air intake centrifugal ventilators can transport air and other non-flammable, non-toxic, and non-corrosive gases to steel. The gas must not contain viscous substances, and the dust and hard particulate matter should not exceed 150 mg/m3. The gas temperature must not exceed 80°C. These fans feature excellent aerodynamic performance, with impellers and pulleys rigorously calibrated for static and dynamic balance, ensuring smooth operation, low vibration, high efficiency, and long service life. They are widely suitable for industrial and mining sectors, large buildings, hotels, and restaurants for indoor ventilation, exhaust, and smoke extraction.