What are common commercial names of transformer oil?

Commercial names depend on supplier, region, and fluid type. Mineral oil product families often include well known branded lines from major oil companies, and ester and silicone fluids have their own recognized trade names. In practice, utilities specify performance standards such as IEC 60296 and then accept approved branded products that meet those requirements. For safety and compliance, the key is not the brand name but the batch test certificate, SDS, and verified conformance to the specified standard and corrosive sulfur requirements.