Vintage Leica attachment: ID, please?
Thanks to the help I received on this forum, I was able to sell my WWII vintage Leica and lenses on eBay. Thank you! The buyer was very happy with the sale, and so was I. A couple of months later I found this item, which is clearly related to the Leica. But before I even try to determine its value, I need to know what it is. I'm sure one or more of you will know. Thank you in advance.
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