... , furniture structure,The following is the square tube specification we can supply Square hollow section tube (mm )Rectangular steel tube (mm)ODWTODWTODWTODWT15*150.6--1 ... requirement.100*1001.2—5.75400*4007.75-11.75Black pipe are usually with anti-rust our black painting on surface ... ,TSAM A500,EN10210,GB/T9711.1-1997, API Material:Q195, Q215,Q235,Q345,ST37-2,ST52-3,S235,S355, 20#etc Diamete20 ...