Thanks all. I though initially that it would be M42 when buying, but it appears the seller made the mistake. The price was lower than the shipping, and overall the quality looks very good, so not in a hurry to return yet.
Additional question, does the "bare" portion of the lens, on top of which the mounts are mounted, has some sort of known name? Maybe it's possible to find only the converters for sale? I'm just not sure what to even search for..
What about the exakta->m42 adapter rings? If I understand correctly, these will not have infinity focus, but for any other focal distance the lens would work properly?
---------- Post added 02-02-21 at 10:06 AM ----------
Another question, could maybe a Pentacon 6 converter fit the "bare" portion of the lens?
For example, would a converter like this one (
Pentacon 6/Kiev 60 Lens to Pentax PK K Mount Adapter K5,K5II,K7,Kx,Kr,Pentax Q | eBay), Pentacon 6 to Pentax K work with this lens?