I bought it from a store after researching on skroutz, to see if they have improved compared to the past, but unfortunately not. My observations are specific, but also for all similar products. After 55 years of swimming in pools and the sea with goggles (chlorine and salt are what ruin the coating), all these products are a waste of money. The only thing that does the real job of not fogging up is what I learned from a colleague a few years ago: I wash the goggles with hand soap (inside, of course), then I put a little plain white toothpaste (careful, not colored), spread it, leave it for a while and then rinse it thoroughly. Before I go into the pool or the sea, I apply saliva (even with the tongue, since we are talking about toothpaste), but I never put pool or sea water in the goggles. If they get a little foggy due to, for example, the sun, I apply a little saliva on the spot. Simple rinsing with tap water as soon as I finish swimming. With this process, they don't fog up or only slightly due to the sun, and it has been 3 weeks without needing to apply toothpaste again. Try it.