That is likely the location for the European wiring connector to be located. They have much different hitch set-ups and a much different standard round plug. Fro what I saw while in Europe last month, most are mounted right to the back bumper of car in about the position where that little removable cover is. Here is a picture of one from a VW
EU PLUGYou will have to add a brake controller and get a 4 flat to 6 round adapter and wire your brake controller into that. Here is an example of one
4 flat to 6 round & 4 flat