certificate Factory Capacity We, Doorwin, as manufactrure, are focusing in high-end solid wood, aluminum & wood windows and doors, which has the capability( 50,000 square meters per year) of design and production with a full range of professional production lines. Our Germany imported equipment to make sure the precision to 0.1mm gap. And we have CE international certification for exporting our products to Europe, North America etc.Doorwin as a windows, doors specialist in China, is qualified to supply you a wide range of windows & doo