Leica M39 to Hasselblad adapter?

Hey guys. I just found this on a site I was browsing and was intrigued:

http://www.fotodiox.com/shop/product_info.php?cPath=27&products_id=716

So I guess it's saying that M39 lenses will fit onto a Hasselblad with this adapter? But will they work? I'd be interested in checking it out, but I would want it to actually be functional. Wouldn't there be an issue using a lens intended for 35mm on a Medium format camera?

Any information would be appreciated!

The thing is made for Visoflex-lenses, i.e. lenses that are made to have the Visoflex housing between them and the camera, not the regular lenses.

There are two major issues with lenses made for 35 mm format:
- They lose infinity focus, because the distance between lens and film is longer on MF cameras (which is why Visoflex lenses could work)
- 35 mm format lenses do not cover the larger formats, so you'd get extreme vignetting.

The second of the two is not necessarily true for all 35 mm format lenses. And it is helped a bit by the first problem, since the projected image circle increases in size when you move the lens away from the film.
But Visoflex lenses are not just made for 35 mm format, but also to be further away from the film. So i wouldn't trust that you would get anything but a small circular image inside the Hasselblad's 6x6 format.
However, using a Hasselblad A16S magazine, which produces a 4x4 cm format, will probably work without a problem, as far as coverage is concerned.