1) Q195, Q215, Q235, Q345; 10#, 20#, 45#; 2) STBA25, STBA25, STBA26; A53(A, B), A333, ... -- Material of Welded Square Pipe: 1) Q195, Q215, Q235, Q345; 10#, 20#, 45#; 2) STBA25, STBA25, STBA26; A53(A, B), A333 ... metal, easy installation. It is mainly used in constructing professional medical instruments, upscale furniture, automobiles, airplanes, subways, ship buildings and so on ...