Modellbahnshop Lippe has a wonderful photo on their homepage showing new Märklin Erz Id cars:
I've long been a fan of Erz IIId cars and have 10 Fleischmann 5520 cars, but am intrigued with these Märklin cars. I read somewhere that the Roman numeral refers to the height of the wagon walls. Is this true? I'm also wondering during what years these were in operation on the DB (and for that matter what years the Erz IIId cars were in operation as well).
Thanks in advance.