I think I still have an old dumbbell spanner somewhere. They used to be the default in Germany when I was growing up, perhaps because they were an early form of multi-tool. They're called 'bones' in Germany, though. This looks as if some cheap stuff from the Continent was re-packaged?
I won this in the quiz section of our middle class dinner party / drinking sesh on NYE. Seems relevant.
More scrap for the scrap metal guy...
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