... 1.0/1000 UsageApplicable to hydraulic pressure, pneumatic cylinder,oil pump barrel, motor body, transmission ... SAE 1026, SAE4130,SAE4135, SAE4140, 27SiMnSize Processing Cylinder diameterLength /mmStraightnessSize accuracyWall thickness/mmInner boreroughnessCold-drawnID28~ ... Test, Blow Test, Impact Test etc), Exterior Size InspectionSKYPE: samsonhuang22 honed tubes for hydraulic and pneumatic cylinder