... .SEAMLESS steel tube, 2. Production based on DIN2391, EN10305-1, EN10305-3 , 3. High precision on the tolerance of tube size ... surface and outside surface. We strictly execute precision tube production standard, each production stage can be traced ... .Steel grade: ST35, ST37, ST45, ST52, E235, E355.Tube OD: 5-80mmTube WT: 1.5-8mmCondition: BK, BKW ... with goods. EN 10305-1 precision seamless steel tube