... 0mm 2. Advanced Roller Extrusion equipment line. 3.CE,ISO Hollow Square Steel Tube 1. STANDARD:GB/T3094-2000, GB/T6728- ... 45#, Stainless steel, Seamless steel, Alloy steel.3. SURFACE:Bared, Galvanized, Oiled, Color Paint, 3PE; Or Other Anti-corrosive Treatment.4 ... ship manufacture, container, tricycle, tower crane.6. SPECIFICATION: SQUARE TUBE(MM) THICKNESS (MM)SQUARE TUBE (MM)THICKNESS(MM)20*301.5-3 ...