The high solvency also allows them to improve the seal compatibility, something of great importance in many applications, such as hydraulic fluids and gear oils. Their outstanding low temperature properties help naphthenic oils to improve the low temperature properties of the lubricant formulations where they are used. Moreover, naphthenic base oils are available in a wide range of viscosities, ranging from very low viscosity products extensively used in aviation hydraulics, to high viscosity products more suitable for applications such as industrial gear oils