Automotive manufacturers have all gone with plastic or lexan (a type of plastic) lenses. Lexan is
harder and lasts a little longer, but the problem with any plastic part that is exposed to the
elements like the hot sun, is that they wear fairly quickly. The average useful lifespan of a plastic
headlight lens is only 3 years. After that they become cloudy and yellow as a haze builds up on
the outer layers. This haze makes it so that light emission and brilliance is greatly affected and
night time driving safety is at great risk. Another factor is acid rain damage, which will show a
marked division between the upper and lower layers.
Acid rain etches the plastic and as it evaporates it becomes more caustic and usually etches the
bottom half of the lens. Mobile Auto Doctors headlight resurfacing process will remove acid rain
etching, pitting and deep scratches from road debris and harsh weathering as well as removing
the cloudy yellow look of the headlight.
Before:
After: 
You should also know that headlights are a Virginia State Inspection item. Specifically item
number 5 of the State Inspection checklist.
So do yourself a favor and let Mobile Auto Doctors take care of those cloudy, yellow headlights
before you have your vehicle inspected. Save yourself the return trip for a re-inspection!!