I thought it would work well for covering the cardboard window blockers I made to keep the sun out while parked, it also works well for camping.
I used spray glue on 1 side, turned it over and added small magnets around the edge's then glued another piece on the other side with the magnets in between then trimmed them.
They came out nicer than I thought and totally block out the front.
I need to make some more for the remaining windows. Cheap and easy.