... standard :GB,ASTM ,DIN , 2)grade : 10#,20#,45#,16Mn 3)outer diameter :2-316mm 4)thickness ... .2-12mm SPECIFICATIONS 1)spiral wels steel pipe as per 10#20#,45#,16Mn 2)Standard & material :GB,ASTM , DIN ... diameter :2-316mm.thickness :1.2-12mm,length :5.8m,6m,11m 4)method of galvanizeation : cold drawn ... 5) surface: print protect,ends beveled or other dealing ...