Firstly, it is environment friendly: it does not contain the harmful chloro-fluoride to damage the atmosphere, and it is conforming to the ISO14001 international environmental protection requirements. Therefore, it does not have any harmful effect on the human body. Secondly, it has a long service life: It is weather bearing, anti-aging, flame resisting, static electricity free, transparent, silk fleeing free, distort free and ultraviolet ray resisting.