Combitronic Heater from Eberspächer
2 Models are available in 12v for Motorhome use
E6610 CTO3 MD Deluxe
E6611 CTO3 MS Standard

The difference between to 2 kits is the standard kit has normal controls and no
230v Heating.
The deluxe kit has Digital controls and 230v Heating
The heater unit is normally mounted outside the vehicle, the matrix colorifier and header tank are mounted inside the vehicle. Ducting can be run to other parts of the installation