... Q345B 3 certification:ISO9000:2000 1)Product Name:galvanized square steel tube2)Place of Origin:Tianjin China ... )Application:Widely used in water supply, construction support, mechanical tube, etc.8)Export: Europe, North America, ... professional production of square tubes, rectangular tube, galvanized square tube processing, hot dip galvanized rectangular tubes, square tubes of large diameter, export ...