Square steel pipe OD: 30*30mm-800*800mm WT: 3-40mm Square steel pipeSpecification: 30-800mm thickness: 3-40mm material: Q235, Q345, 20#, ST44,ST52, STKR490, ASTM A500 Standards:GB,DIN,JIS1) Dimentions: 30*30mm-800*800mm, Thickness: 3-40mm Length: <13m2) Material: Q235, Q345, 20#, ST37, ST44, ST52, ASTM A53, ASTM A106,STKR4903) Standards: JIS G 3466, DIN EN 10210, DIN EN10219, ASTM A500, GB/T 3094 ...