... Grade: CGCC, Prepainted galvanized steel coils ( steel structure roof sandwich panel ):PPGI is the material which uses galvanised steel ... : 3. Usage of Prepainted galvanized steel coils :Outdoor: roof, roof structure, surface sheet of balcony, frame of window, door, ... door, isolators, frame of door, light steel structure of house, sliding door, folding screen, ceiling, internal decoration of toilet ...