To purchase this anti-fog spray, checkout my Amazon Storefront.
This is a great (not perfect, as some fog will creep in on the corners if you do not apply properly or if you try really hard to fog it up) anti-fog spray for those of us who have to wear glasses and masks.
You will only need one spray per lens. After applying rub it in a circular motion with a soft cloth. I promise you will notice a huge difference!