... Commodity:Cold Rolled Square Tube(Steel square pipes,rectangular pipes).Material:20,10,45,35# and Q235,16Mn, 40Cr, 35CrMo. Standard:ASTM A106, ... A53, A1045, A210 and A5140,DIN st42, st45, st35, st37 and st52, JIS G3461, G3455, G3456 ... and G3454,GB 8162 & GB 8163 Steel Square Tube, Cold rolled Hollow Section