Driving back from Phoenix, it got a little cold in the RV. The windows needed some insulation. Reflectix was the best answer, since it will keep out the heat on the summer as well. But, being me, I had to make it pretty. It took a little less than one roll of Reflectix and three rolls of peacock feather Duck tape to make screens for the five windows and three vents. I have more Reflectix that I can use for the driver's and passenger's doors, but I think I will need more for the windshield. I have two more rolls of Duck tape, though!