Plastic drainage boards are made by stamping plastic base plates made from polystyrene (HIPS) or polyethylene (HDPE) into conical bosses or reinforced ribs (or hollow cylindrical porous shapes). Through continuous innovation and development of the raw materials, there have been significant improvements and transformations. Now, they are produced with (), resulting in greatly enhanced compressive strength and overall flatness. The width ranges from 1 to 3 meters, and the length is from 4 to 10 meters or more.