Detailed Product Description Features of square Steel Pipe: 1)Type: Carbon weld steel pipe of SSAW, LASW and ERW. 2)Material: SPHC, 08AL, 08F, HG5, DF08, Q195, Q215, Q235, Q345, STK500, or per the buyers demand. 3)Standards: ASTM, JIS, DIN, EN, BS, GB. 4)Size from 20mm*20mm*1.2mm to 600mm*400mm*16mm