What are oil filled radiators filled with?

Oil - obviously - but what type and specification?





.... And is there supposed to be an airspace - or filled right up?What are oil filled radiators filled with?
hi..! I think the bigger the engine the thicker the oil?it has further and bigger parts to cover.I tried finding it under oil for radiators,but they want you to buy,buy buy.I also think that there's some kind of filtration system ,one with air an straw like filters on the bottom?I tried,not really my field..good luck on your quest! blessed be...!What are oil filled radiators filled with?
This is the best that I could find , it is from the link at the bottom. I suggest that you contact the suppliers of your radiator and ask them your question.





';The most obvious reason to purchase a oil filled radiator heater is for safety and a


silent operation. These heaters operate by warming up a special heat-conserving


oil inside the heater.';