Seamless steel pipes used in steel construction. 1) Dimentions: 30*30mm-800*800mm, Thickness: ... , DIN EN 10210, DIN EN10219, ASTM A500, GB/T 3094-2000, GB/T 6728-20022) Material: Q235, Q345, 20#, ST37, ST44 ... A106,STKR4907) Plain or beveled ends Seamless Square Steel Pipe used in construction