Raw Material Analysis Aluminum Completely new extrusion from Chinese TOP brand,the best powder coating from Interpon,30 years' warranty without rusting Polycarbonate sheetChinese TOP Brand 100% German raw material with 50μm UV Coating (10 years' warranty on aging or yellowing,CE certificated & test report available) System accessories Chinese TOP Brand rubber seal,304 stainless steel for structure steel and installation screws