Hi Ray,
It might have been but wasn’t! Seen references to it on many US sites but the one that I had in mind was the Mechanic in a Bottle which is being distributed in the UK by Rochfords. Had a chat with them yesterday and it seems that the “cure all” product will be freely available Over the counter but the fuel test kit will only be sold as a merchandising package to participating dealers.
I guess the thinking is that dealer tests the fuel and convinces his customer that he desperately needs the fuel treatment. Which is a shame as I would have thought that the tester would sell equally as well as the preservative will?