The ventilation phenolic board is usually composed of phenolic foam in the middle layer and embossed aluminum foil in the inner and outer layers. There are also single-sided color steel phenolic duct panels, double-sided color steel phenolic duct panels, and special flanges and other accessories that can be made into phenolic composite ducts for central air conditioning ventilation. In terms of bending resistance, compression resistance, and processing performance, it is very good and basically meets the requirements for the use of air conditioning ventilation pipes.