VEVOR Diesel Air Heater, 12V 2KW Diesel Heater with Remote Control and LCD Display, 10L Fuel Tank Diesel Parking Heater, Rapid Heating for RV Trailer Camper Van Boat
Please see the picture in below link for reference, the link is valid in 3 days:https://we.tl/t-CWdFiqMwvW. They are vertical, separated, and horizontal respectively.
It can be connected to the fuel tank, and the machine has very low fuel consumption, about one liter of oil in 4 hours, and there will be no situation where the fuel tank is emptied to the point where the car cannot start.