SS400 carbon steel coil is a Japanese standard carbon structural steel coil, which complies with JIS G3101 standard and is equivalent to domestic Q235B material. Its carbon content is ≤0.22% (some say ≤0.30%), manganese content is ≤1.40%, phosphorus and sulfur content are both ≤0.050%, yield strength is ≥245MPa, tensile strength is 400-510MPa, and elongation is ≥21%. This product has good weldability, is easy to process and shape, and has low cost. It is widely used in building structures, bridges, vehicle manufacturing, mechanical parts and general engineering fields, and is an economical and applicable basic steel choice.