Rob wrote:

It's difficult to tell - he's just written back and said that he's
fulfilled his legal requirements (the name was correct, the
concentration was wrong)

That's ********. If he offered "Isopropyl alcohol 99.4%" and you bought
it as such, then that's what it has to be. I would imagine suing for the
cost of replacing his scented water for the right stuff would be an
open-and-shut case.

Not that a lawsuit is necessarily the right approach for such a small
issue, but it is an option and one worth mentioning if he remains arsey.
A Moneyclaim Online case is what, about £30? Which he pays when you win.

Pete