ZURNPREEM is engineered for modern hydraulic systems, bearings and gears and is available in any ISO viscocity. ZURNPREEM 21A is engineered for use in modern low- and high-pressure hydraulic systems. It provides superior resistance to pump wear, prevents rusting of ferrous metals, and decreases thermal oxidation degradation of the hydraulic oil; all are essential in high-pressure, high-speed, close-tolerance pumps, machines and control circuits. It is ideal for use in vane, axial, piston and gear-type pumps of most control systems and meets the OEM requirements of most manufacturers. ZURNPREEM 21A is formulated with high-quality petroleum stock blended with select rust and oxidation inhibitors, anti-foaming agents and anti-wear additives, providing excellent performance in modern hydraulic systems. It exhibits superior demulsibility characteristics, making separation of hydraulic oils from water in most central system reservoirs and in-plant waste recovery systems readily achievable.