Plastic window material mainly is high density polyethylene, with light weight, beautiful appearance, acid and alkali resistance, corrosion resistance, ventilation and other advantages, is a kind of adding anti-aging, anti ultraviolet and other chemical agents as the main raw material, has the advantages of strong tension, heat resistance, corrosion resistance, easy processing of waste. By covering the construction of artificial barriers in scaffolding, pest out of their networks. This screen is mainly used for vegetable virus-free plantlets after cover function.