UV or Heat damage from halogen lights.

I wonder what ages and deteriorates the Headlight lens the most?

1) Rear tail lights are plastic , the bulb is less watts.

2) The front headlights are Low/High Halogen lights with a lot of watts and Heat.

I think just, because of Heat on the lens during night driving can start the premature aging, the UV rays amplifies the aging effect.

Yes- There is restoration kits for Headlights, and you can put protective coating, but how long is it going to last.

Mine are almost 10years old, exposed to NC weather all year, and are in good condition.....

See H3 Bulbs

http://www.automotiveforums.com/vbulletin/showthread.php?t=968234

Use a Vinegar, water, and baking soda solution to polish head light lens using a news paper.