Some of the old VW Buses came with louvered windows, or jalousies, but Vanagons come with sliding windows. Several Vanagon owners have adapted the old louvered windows, or made some of their own. There are several examples over at The Samba, and I decided to post a few.
Most people hack the front window, but this guy hacked the rear window.
Here are views from the outside and the inside. Although there is more wind noise with jalousies, they allow much more comfortable temperatures while camping.
Here’s another rear window hack with rivets. Very nice!
And one more for good measure.
