I spray, rinse with seawater and wear the swimming goggles. The longest continuous period I have used it is 2 hours of swimming, while with the spray of another well-known company, the goggles would fog up after 45 minutes.

Very good product.
I used it for the first time, after other products (toothpaste, mouthwash, etc.) had no effect.
For over an hour of diving that I used it, the mask's glass remained crystal clear, it didn't fog up at all.
I recommend it.