... .Light in weight, heat insulation 3.Installation is con Polystyrene sandwich panel for sale:thickness0.2~1(mm)Effective width950 ... and lower layer: uses color steel boardMiddle: polystyrene foam board or polyurethane foam boardThe polystyrene density5,6,8,10,12,14,15,16 ... , upper layer is steel sheet, the inner layer is Polystyrene foam plastic, the bottom layer is also steel sheet.2.These ...