As a specialty paper, black on both sides. Black cardboard is characterized by fine, xinhei, strong thick, good folding resistance, smooth surface, stiffness, tensile, burst strength higher. Commonly used thickness 120 g-350 g of black cardboard. Because of the black paper jam inside and outside is black, so I can't print color patterns, silver is only suitable for hot, hot, and so on. Made out of a bag is also very beautiful.