... 0.3-1.0/1000 UsageApplicable to hydraulic pressure, pneumatic cylinder,oil pump barrel, motor body, transmission shaft, etc ... 34CrMo4, SAE 1026, SAE4130,SAE4135, SAE4140, 27SiMnSize Processing Cylinder diameterLength /mmStraightnessSize accuracyWall thickness/mmInner boreroughnessCold-drawnID28~OD400≤12M0 ... Test etc), Exterior Size InspectionSKYPE: samsonhuang22 hydraulic cylinder tube st52 din2391