Hydraulic cylinders used in construction equipment use high-pressure (35 MPa) hydraulics under extreme working conditions, and in order to prevent leaks and other problems, seal housings and other precision parts must be machined to micron-level tolerances. To ensure the strength of our products, we use high-tension steel as well as other new materials and technologies needed to fulfill our customers' requirements. That's the stuff that Koretsune Seiko hydraulic cylinders are made of.