Thermadore Aircons

Can someone please give me some details on those 'Thermadore' aircons that some people have fitted to their bugs?

I am not after one, the subject came up at work about what these things are, etc. I'd love anything you could tell me - what type of aircon are they (evap, etc), how they work, they were obviously an option, but for what years? Do they fit on all makes, or just certain cars?

And.....how many are around today, what are they worth, etc. Pics would be great too, so I can pass the data on....

Thanks!

They are evaporative coolers - "swamp boxes"

Work on the same principle as putting a wet towel over your face and standing in front of a fan.You poor water into them and the air rushes in the intake and over the "straw" fill.

Work great in dry climates eg Broken Hill.
Work crap in humid places. too much moisture in air for evaporation process.

In fact i would be wary of nasties breeding in them in warm humid areas.