It says: Do not exceed trailer tow ratings of 6000 lbs trailer weight and 600 lbs tongue weight, plus a lot of legal mumbo jumbo, like don't use unauthorized BMW cell phones while towing, and heavy or overweight passengers may reduce your towing capacity, and my favorite- use of cartoon character tow hitch covers may void BMW warranty.

OK- just kidding on the legal stuff. It does say in small print not to modify, drill or weld your tow hitch and that trailer brakes are not connected (which makes me wonder if there is a BMW trailer brake kit?).