Susan,

Excellent topic. Surely that would help. An even more effective and still fairly compact and very lightwight alternative would be to carry Reflectix pieces cut with scissors to fit your windows. These easily roll together and I store mine in the car where I keep the windshield sun shade.

This is a favorite tactic of Honda Element owners who camp in their vehicles. The Reflectix pieces, cut slightly larger than the windows, fit snugly simply by compresssing the edges into the window openings.

I've done this and it is striking how much cooler the car gets in the morning the moment you pull the Reflectix pieces down. A fellow on the Element forum posted this week about an overnight trip he did to Mammoth Lakes where it got down to 12 degrees at night. He slept in the Element and used Reflectix in the windows.

The Reflectix is great for camping in the car as an insulator and for privacy.

Cheap, too.

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