... and polyurethane Color: white-grey ,sea blue,red, silver, polyurethane sandwich panel (PU)Material: steel and polyurethane Color: red, silver, blue ... on. 1.Structure: Upper and lower metal exterior sheets sandwich panel with the PU foamed.The exterior metal sheet can be color ... to customer’s request Recommend coating PE, HDP,PVDF polyurethane sandwich panel(PU)