C channel is made of galvanized steel strips by the method of cold-bending formed.The surface treatment are galvanized or bare. It has many advantages compared with traditional structural steel, such as light weight, excellent performance cross-section, high-strength and so on.
A sandwich panel is one structure made of three layers of material: low density core inserted material in between two relatively thin steel skin layers.
The up & down surface of this rockwool panel is Galvanized & Pre-painted steel sheets, core material is 5 components rockwool glue, it is formed by heating, foaming & laminating.