Elegance and beautiful shape , modern and practical design , having scientificalness and personality . having automatic dustproof system in it , dust eliminated when the window screen operated Screen Fabric: All use Phife Screen of the highest quality , which are avirulent insipidity , anti-corrosion , antiflaming , easy clean , ametabolic , longer service life . Spring : Material is Mn 65# , which surface is processed by Dacrolon-tech. It doesn’t rust . and nimble and light to use. Accessories : Material is PA6 , excellent mechanical strength and toughness , and chemical resistance , dimension stability , low dilatation . Aluminum Alloy Profile : Material is 6063-T5 of high intensity . Oxidize , Heattinting , Spray powder are available . Many colors are at your choice .