1.Materials: geomembrane,geotextile 2. Property: Flexibility is good, exception of a geotextile's isolation, drainage. Composite prevent & drainage board(drainage board, filtration board)HONGXIANG composite drainage board is a dimple geomembrane,which produced by extruding plastic sheet into dimple shape. These dimples, in spatial structure with centain heigth, can resist long-term high pressure ...