... .6.High brightness on both inside surface and outside surface.7.Superlow roughness on both inside surface and outside surface. We ... : ST35, ST37, ST45, ST52, E235, E355.Tube OD: 5-80mmTube WT: 1.5-8mmCondition: BK, BKW, BKS, NBK, GBK.Management standard: ISO9001 ...