1)Galvanized steel tube 2)Outer diameter ... 4)standard:BS1387,ASTM,GB,DIN,API Galvanized steel tube for hot dip,pre and electric Products Details ... :1) Round steel pipe: Size from 12mm to 325mm, thickness 0.6mm - 12mm2) Square steel ... 6mm, 8mm to 16mm,28mm13) Cold rolled steel strip: Width from 32mm to 685mm, thickness ... best to help you! Galvanized steel tube