Cylinder Honed Tube/Hydraulic Cylinder Honed Tube Grade: ST52,ST52.3,CK45,E355,16Mn,STKM13C,SAE1020 Cylinder Honed Tube/Hydraulic Cylinder Honed Tube Grade: ST 52,ST52.3,CK45,E355,16Mn,STKM13C,SAE1020 ... ): < 0.8 MicronType: BK+S,high precision cold drawn,seamless honed,burnishedHigh precision cold drawn tube(ready to honed tube) can also be supplied.