Full disclosure - I may have just made that term up. Our pu has the rooftop ac but that's where all the air blows, back up on the ceiling. It certainly cools the pu but it would be much more comfortable if some cool air would blow downward and I think we wouldn't have to run it as much/high. It has the factory diverter in the vent opening but it doesn't help much for this purpose. I can't find anything specific so willing to DIY. Any ideas? Something akin to the exterior vent for a clothes dryer and some heavy duty adhesive maybe.