They meet the stringent requirements of hydraulic systems using high pressure, high output pumps as well as other hydraulic system components such as close clearance servo-valves and numerically controlled (NC) machine tools. The products exhibit outstanding oxidation and thermal stability allowing long oil life and reduced deposit formation in harsh conditions and with severe hydraulic systems using high pressure, high output pumps. The keep clean performance helps protects critical hydraulic system components from malfunction, such as tight tolerance servo and proportional valves found in many modern hydraulic systems.