was made with gel coat on the outside of the trailer. Gel coat protects the fiberglass and resin construction ( composite ) from UV rays which would deteriorate the composite construction of your trailer shell. Gel coat is made with the same type of resin base as used in the composite of your trailer. Instead of fiberglass for support the gel coat uses UV protectants, mineral fillers, tinting for color and flex agents to make the outside of the composites more durable.
Basically the factory takes a mold and waxes the inside of the mold. They then spray in a thin layer of gel coat. On top of the gel coat they apply resin and fiberglass and build that up to the desired thickness. then they cure or wait for it to cure to a harden shell. They pop the harden shell out of the mold. When the shell is out of the mold the Gel coat is now on the outside. It looks smooth and shiny and the outside is finished ready to be used.
The outside color layer is the gel coat that could have been tinted almost any color from the factory. In the case of Scamp
it is white.
If you keep this surface clean and waxed it can last almost forever. If you neglect this surface it turns a flat color and gets chalky (dust like film on the surface) this can be polished back to a high shine at least until you wear through the gel coat.
once you wear through you expose the glass and resin below to UV and they start to deteriorate fairly rapidly. This inner layer has a greenish to yellowish semi clear layer.
When the Gel coat wears off allot of people have the outside of the trailer painted. You could re shoot the gel coat but it is so laborious and expensive almost no one does it except for small repairs.
Some of us with worn gel coat choose a temporary repair to our thinning gel coat by cleaning it thoroughly and putting several coats of Zep floor wax to bring back the new gel coat shine. This coating is fairly easy to apply and last a couple of years if the trailer is stored outside.
This is kind of a basic break down. Hope it helps with your understanding.