What do we usually mean by 250 grams of grey cardboard?Many customers will misinterpret it as the weight of a sheet of grey chipboard. In fact, the weight of grey chipboard refers to the weight of paper per unit area, which is generally expressed as how many grams per square meter.There are also in foreign countries how many pounds or how many kilograms of paper per token, can be converted to how many grams per square meter according to the length, width and number of sheets per token.Therefore, paper is sold by weight.But domestic grey board, usually there is a deviation, so the goods on the market are rarely by weighing way to acceptance, which is based on the domestic production of grey board, but grey chipboard and thickness, there will be some relation between routine for 100 g = 0.16 MM, so we also can be calculated according to the thickness of gray chipboard g, this is the general, the thickness of the conventional grey board standard on the market, but for some of the high density of grey board, due to the tight degree is high, the same g board thickness will be some corresponding slants thin, mainly related to the density of board ~