Spiral Duct, Air Vent, Flexible Duct manufacturer / supplier in China, offering Polyurethane Foam Thermal Insulation Board with Aluminum Foil Paper, 3 Inch Rigid PU Foam Insulation Panel with Foil Facing for Building Wall Envelope, 2 Inch Thickness PIR Foam Insulated Board for Energy-Efficient Wall and Roof Systems and so on.