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There are two types of rock guards, the rock guard for the windows, and the rock guards for the front of the trailer near the tongue. You can get either or both, from Airstream, or Inland RV, depending on the year of your trailer. The one that goes over the windows is smoke colored Lexan, and the ones for the body of the trailer are stainless steel.
Meddle not in the affairs of dragons, for you are crunchy, and taste good with ketchup.