... . the best quality Product typealloyAlloy statusSpecification(mm)Executive standarddiameterWall thicknessThin-walled tube1,3,5seriesO,H14,H34,H326~1300.5~5GB/T68932 ... ,6,7seriesO,T4,T66~1300.5~5GB/T6893Thick-walled tube1,3,5,8seriesH112,O,F20~1805~40GB/T4437.1GJB23812 ... ,T4,T6,O,F20~1805~40GB4437GB/T4437.1GJB2381 Extruded aluminum thick-walled tube