... in core. Common panel thickness 30mm, 40mm,Model B: pre-painted steel sheet as outside cover ... EPS foam in core. Common thickness 30mm,40mm,Model D: Aluminum sheet as outside cover, galvanized ... plywood in core. Common panel thickness 30mm,40mm,Model E: Aluminum sheet as outside cover, plywood as ... fiberglass sandwich panel with PU form in core.Model F: fiberglass sandwich panel ,with polyurethane foam ...