This is an ambulance based on an Opel Kapitän. On our trusted coachbuilder's site there is also a PickUp based on Opel Admiral from 1965.
Miesen was founded in Bonn in 1870, since 1905 the focus has been on ambulances. Ambulances, emergency ambulances, mobile clinics, up to large-capacity ambulances based on omnibuses (btw: the German abbreviation for this is the tongue-twister GrKrKw).
But also hearses are part of the programme (a bit macabre, as if you don't trust your own ambulances...), light fire engines, station wagons and various special vehicles.