I have for sale a very nice custom made adapter. It has male M82x1 threads on one end and male M54x0.75 threads on the other. It adds 29mm backfocus. Black annodized and in perfect condition. I think it might be made by Precise Parts but I can't be sure.
This would fit for example the large M82 Riccardi reducer and attach to an Atik OAG or Atik EFW2 filter wheel, but any device with these threads will work.
