... pre-insulated HVAC duct Material: phenolic/PU/PIR foam+aluminum foil/galvanized iron HVAC duct use the phenolic, PU, ... , both side with 80micron thickness aluminum foil, or one side with 80 micron thickness aluminum foil, the other side with 200micrion ... thickness galvanized iron. Specification:1. Standard size: 3950*1200*20mm (usually for 40HQ container) ...