Back in the 50's owners of station wagons would open the back window while driving to 'let in a breeze' - problem is it drafted in the car exhaust gas, and killed the kids riding in the back of the station wagon.
Now days the car exhaust is typically a lot cleaner, and not nearly as much carbon monoxide, the tasteless and odorless gas that killed a lot of people - even last year due to leaking heat exchangers, and poorly vented gas appliances.
I would not want a vent in the rear window. If you have a van, cut a hole in the roof, and use a Fantastic fan. They do not consume a lot of power, and have a quiet fan that moves a LOT of air! I have 3 of them in my motorhome. A little rubber roof sealant, and the job is done, and will not leak!
I might install one in my cargo van that I will be getting this summer. I can run it while it is parked in the sun, using the solar panel that I will install to run it, and keep it cool all day long.
Fred.
Money can't buy happiness but somehow it's more comfortable to cry in a
Porsche or Country Coach!
If there's a WILL, I want to be in it!
I havn't been everywhere, but it's on my list.
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