Vytac got this howto video to show you how to properly fix the Valken Sierra Goggles... "In this video, I will show you the modifications I did on my Valken Sierra Goggles. The goggles did not go by their promises, one of them being that they fog while they have thermal glasses. The problem was that the goggles had a lack of ventilation. I solved this problem by soldering several holes on the top and bottom that still are too small to make a bb go through and safe enough.

Thank you for watching."