... ,GB Grade: CGCC, Prepainted galvanized steel coils ( steel structure roof sandwich panel ):PPGI is the material which uses galvanised ... Prepainted galvanized steel coils :Outdoor: roof, roof structure, surface sheet of balcony, frame of window, door, garage doors, roller ... wagon and so on.Indoor: door, isolators, frame of door, light steel structure of house, sliding door, folding screen, ceiling ...