Hi Volker.
I found it on e-bay:
http://search.ebay.com/Hasselblad-M...refZC6QQfromZR4QQsacatZ625QQssPageNameZRC0021
I bought the less expensive one made in Japan ... and it works fine. The Fotodiox one is a lot more money. I don't know if it is better made, but it functionally doesn't do anything more than the less expensive one.
You lose the aperture coupling, and will have to stop down meter and shoot ... but you gain focus confirmation in the viewfinder and a maximum shutter speed of 1/4000th for shooting wide-open in bright light with lenses like the Zeiss 110/2F or FE for example. If this is the only use you will have for the Zeiss lenses, you can buy 200 series F lenses for a LOT less money than the FE versions. All C, CF, CFi CFE, F and FE lenses will work.
I recommend V lenses like the F or FE 50/2.8, 110/2, 150/2.8 and 65/3.5 CFi, 100/3.5 CFi, 180/4 CFi. Tip: when using this adapter, be sure any Zeiss lens is cocked after removing it from the adapter before using it on a Hasselblad camera.
I also swapped out the Mamiya 645 focusing screen for one with a split microprism screen to facilitate manual focusing of V lenses ... which is available from Mamiya through B&H, etc. It still retains AF ability with Mamiya AF lenses.
Pretty sexy set up IMO.