... as steel (mill black and hot dip Galvanizing)and stainless grating flooring walkway, platform and steel structures, stair tread, ... trench cover, compound gratings, storage shelves, ladder, fences and handrail so on for construction project, oil project, seaport, ... David Huang)4Material GradeASTM A36, A1011, A569, Q235, S275JR, SS304, SS400, Mild steel & Low carbon steel, etc 5Surface TreatmentBlack, ...