You can also improve your headlights by polishing the clear plastic covering with toothpaste or a commercial polish that does the same thing.
https://www.google.com/search?q=clean+headlights&ie=utf-8&oe=utf-8
I gotta do that about every four months. Worked well the first time but each time now it takes less time for it to get foggy again. I can't afford a new lens right now.