... made in China including Steel pipes, square steel pipes, rectangular steel pipes, galvanized steel, galvanized square, rectangular tubes, spiral steel pipe.We export our product ... ,DIN,ASTM,JIS,Steel GradeQ195/Q215/Q235/Q345/10#/20#/45#Zinc content40-500gPer m2Tolerence of outer diameter±0.3mmQuality1)Special design ... South America,Eastern Europe,Southeast Asia,Africa Round hot galvanized steel tube