The air vent in our “bedroom” is located right above the bed. Everyone, including the critters sleeps very well in the RV and we tend to sleep in if we can. This can sometimes pose a problem when the sun rises and the RV isn’t dark enough to sleep anymore.
We had some of this “Reflectix” material left and I made some quick and easy vent covers that help keep the sun out and even helps with keeping the rig warmer/cooler. PLUS it helps with condensation on cooler nights