... guarantee 4)7 year experience 5)material:45 cr+40 chromed plated ApplicationExcavator Hydraulic CylinderMaterial45# Steel & 40CrDedigned ForDouble Acting,Single Piston RodSeal ... TypeNOK,PARKER or as per your needsPiston RodHard Chrome/Nickel plated,ground&polishedTubeHigh tensile cold drawn tube,precision honed for extended ...