ESPRO RPO 543 is a type of rubber process oil that belongs to the naphthenic category. Naphthenic rubber process oils are known for their excellent solvency, good low-temperature properties, and low toxicity. These oils are commonly used in the production of rubber products, such as tires, conveyor belts, hoses, and shoe soles, to improve their processability, mechanical properties, and durability.ESPRO RPO 543, specifically, is marketed as an all-purpose rubber oil, which means that it can be used in a wide range of rubber formulations and processing methods. This oil is formulated to have good compatibility with various elastomers