Heat transfer fluids are a much wider concept than heat transfer oil.
If we are talking about a heat transfer oil, the use is limited from about -115 °C to + 400 °C.
For the use of heat transfer fluids at a higher temperature, we are actually talking about molten salts up to 540 °C and liquid metals up to almost 1000 °C.
Rodun Benelux BV mainly moves within the range of + 400 °C and only owns with thermal oil types.