compositeair ductShanghai Hongji is the first technology-based company in China that specializes in the research and upgrading of air conditioning duct systems, using specialized materials such as installation and construction duct flanges, PVC flanges, aluminum alloy flanges, and inserts. With the most advanced technology, excellent quality, and comprehensive products, the company actively builds the first brand of composite ducts in China. PVC flange is the most indispensable air duct connector in composite air duct systems, which directly affects important indicators such as air leakage rate and service life of the air duct system. The PVC flange has passed strict laboratory testing and practical inspection, and is the most rigorous component of the Youshi brand.

We promise that our PVC flanges are produced from non recycled materials and can meet the B1 flame retardant standard. This product is used for connecting cold and warm ventilation ducts, central air conditioning phenolic aluminum foil composite air ducts, extruded sheet aluminum foil composite air ducts, color steel plate composite air ducts, etc. The product has the advantages of beautiful appearance, convenient use, environmental protection, flame retardancy, and low price. The product specifications are diverse, and the most economical solution is tailored for customers.
Youshi adheres to its consistent professional attitude and works together with our partners to provide customers with higher quality and cheaper products.