... quality control 3. Scientific container loading Name:Steel Square/Rectangular Tube (Hollow Section)Standard:GB/T6728-2002,ASTM A500 Gr.A.B.C ... CoilMain Steel Grade:Q235,Q215,Q195 Size:Square:10X10-400X400MM, Rectangular:10x20-200x400MMWall Thickness:0.35-3.0MMLength:5.8M,6M ... .0-12.0400x4005.0-16.0 200X4005.0-12.0Square/Rectangular tube is applicable to frame for civil construction, furniture and ...