... Steel Tube Material:Q235,Q345,10#,20#,X80, Standards:API Spec5L/5CT,GB/T9711 OD:219-3000mm thickness:6-25mm Spiral Steel ... offer based on good quality Qingdao Sino Steel Co., Ltd was one large Steel Holding Company, as a window of ... foreign trade of Chinese Steel industry.If you have some new requirement,please don ... the competitive price based on good quality!! Spiral Steel Tube