You can buy rolls of the window film in several different sizes, according to your needs. This small roll, which is 17.5 inches wide and 78.7 inches long, is only $10.98.

Most UV-blocking films work best when light hits the film at a 90-degree angle. But this isn't practical for window films, which receive light from the Sun at various angles throughout the day.

With costs ranging from $500 to 800, installation of 3M's window films isn't exactly cheap. But if the films deliver all the benefits listed above and can also be proven to net better fuel mileage ...

According to National Glazing Solution, window film can successfully block up to 99.9% of UV rays.

That’s why in areas of the country where the temperature is in the triple digits, a UV-blocking window film might not be enough to cool a room on its own (though it’s still worth a try).

Professionally installed window film typically reduces exposure to UV radiation by up to 99%, reduces glare, interior fading and hot spots, according to the group.