... H8 Straightness 0.3-1.0/1000 UsageApplicable to hydraulic pressure, pneumatic cylinder,oil pump barrel, motor body, transmission shaft, etc. ... Quality Standard DIN 239, EN 10305 and ASTM A519 ProcessRaw materials- Cold ... Test, Impact Test etc), Exterior Size InspectionSKYPE: samsonhuang22 honed tube for hydraulic cylinder