Looks like that wrench was introduced about 1974, if my rusty German is still functioning. Will paste a bit more in a few minutes, gotta walk the dogs (waited 11 years another hour won’t hurt), but confirms Kasiano’s comment on who they were.
Something about a ratcheting wrench made of Chrome Vanadium put it on the screw, (damn snippet view) and
Internet Archive doesn't seem to have a copy.
Google Translate says:
The new ratchet wrench from H Blecher & Co KG Holzen is made of chrome vanadium and can be used universally. The wrench does not have to be removed when looking at it, but keeps contact with the screw. Just by a slight pre-order pulling back the nut in....
Here is the patent for the back end
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Don't trust the translation of the title.