I just acquired a Metz 40-MZ3 with SCA 3502 M4 adapter to use with a Leica 21mm ASPH. I can down load the instruction manual from Metz.de and the flash works on my M7.
My questions are, how many types of SCA 3502 adapters are there and what are the differences?
A link from Nemeng http://nemeng.com/leica/018b.shtml no longer works for a table of the 3502 adapters. Has anyone archived this reference and can share?
I acquired this unit to develop the ability to use a 21mm ASPH with flash on my M7. Of course the problem to be solved is the fact that the hot shoe normally holds the 21mm Finder. I need to have a custom double hot show built and am presently thinking of having the Metz unit off camera and useing the Metz 3000 cord.
Has anyone gone to this type of arrangement with an M7 and 21mm ASPH?
Thanks for any replies and information.-Dick

It is too bad that Cosina discontinued making their double shoe mounts.

Scroll to the middle of the page: http://www.cameraquest.com/voigtacc.htm

You'd need to find a type A model used. I own one (not parting with it) and it solves many problems. You do loss the hot shoe feature of the camera.

Perhaps you can have a machinist make you one after looking at the above web link.