The PandaSolar ballasted solar roof mounting system, made of AL6005-T5 aluminum, features an Adjustable Angle Ballast and is specifically designed for the installation of solar panels on concrete flat roofs. Product Details Name:  Panda Solar New New Aluminum Adjustable Angle Ballast for Flat Cement Roofs  Brand:  PandaSolar Material:   AL-6005-T5 MOQ:  1PCS Lead Time:  Within 12days Product Origin:  Xiamen,China Warranty:  12years Certificate:  CE certification Customization:  Available