... , SAE J524 2. nonoxidizing normalizing 3. E235, E255,E355, St37.4, St35 zinc plated hydraulic tubes zinc plated hydraulic tubes 1 ... .: DIN2391/C, EN10305-1,EN10305-4,GB/T3639, GB/T81733) Steel Gr.: E235, E255,E355, St37.4, St35,St52,St52.4,St454) O.D: 3 ...