... . Certificate: ISO9001:2000 4. Zinc-coating: 213-213g/m2 Name: pipe/ welded square tubeMaterial: ASTM/GB/JIS/BSThe hot finished hollow ... , automobile, container and supermarket shelves, etcThe use of the rectangular pipe: General use load, column, etc. Also used to support structure ... : Mr.VincentTel: 86-21-61364927 Fax: 86-21-61364977 square pipe for curtain wall