Main performance characteristics: ◆Reasonable bell design, low noise, large air volume, strong exhaust force, low operating cost: ◆ Imported bearings, high strength and low noise: ◆ Synthetic PVC shutters or aluminum panel shutters using the principle of air flow are light in weight, non-deformed, flexible in opening, and anti-air backflow: ◆ Multi-reinforced aluminum-magnesium alloy pulley, light weight, high strength and good toughness; ◆There are two kinds of fans, vertical and inclined, to meet the needs of different sites: