Commodity:Hot Rolled Square Tube(Square steel pipe,steel tube) Material:Q235B/Q345B and so on. Commodity:Hot Rolled Square Tube(Square steel pipe,steel tube)Material:Q235B/Q345B 20#,10#,35# ,16Mn, 27SiMn, 40Cr, 12CrMo, 15CrMo, 35CrMo and 42CrMo Hot Rolled Square Tube