I made the mistake of
assuming the adapter came with in the $390 trailering package. Silly me!
Had to go track down an adapter after the fact. Incidentally - I think the adapter only ran me like $30 or so (online)......so if you don't need the 12v power outlet and hitch cover - save you money on that "convenience package" from the dealership. I didn't need the power outlet and thought the rubber hitch cover was kind of ghey anyway. Got myself a nice billet H3 cover off of eBay for around $30.