The product has the following features 1.Can provide a variety of surface treatment methods for customers to choose. 2.Broken bridge three cavity energy-saving design, multiple sealing design. The product has good sealing, watertight, sound insulation performance to meet the requirements of energy saving and emission reduction. 3.The narrow edge design of the inner and outer flat frame, the drainage tank is hidden by the side of the secondary frame and the outer frame to improve the drainage capacity and prevent backpouring. 4.With a variety of opening methods such as double internal opening, the product is easy to process, operate, disassemble and clear, long service life. 5.The integrated structure of the window screen improves the overall resistance strength, high temperature resistance, flame retardant, anti-theft and anti-mosquito.