Free: Contests & Raffles.
Cat Crap! I hear what the guys are saying above about coated lenses and such but that stuff works amazing for glass, goggles, lenses you name it. Would take a lot of work to apply to your windshield....
I was referring to this BUT have never used it.https://www.rainx.com/product/glass-water-repellents-cleaners/rainx-anti-fog/#.XcsMtFdKja8I use a soft cloth and have never applied a fog treatment except to my diving mask.