I came across an exterior vent that looks like it can be used on the sliding
windows of our vanagons.  The link is http://www.maxxair.com/window.html.  JC
Whitney is one company that sells them.

Has anybody on the list tried these?  I wouldn't mind something a little
wider, but this would be better than nothing.  I am looking at an alternative
other than installing some old Type II crank open windows.

Thanks for any input.

Later