Filon, Gel coat filon, High Gloss Fiber glass. Three different things and different process. The compartment doors are NOT High Gloss fiber glass. Low end campers will use Filon and they will yellow in time. Higher end campers use Gel coat filon and with proper care and Maint will not yellow, The Montana uses High Gloss fiber glass on the front and rear caps and gel coat filon on the side panels..they offer the optron of High Gloss Fiber glass over all, execpt for the doors,
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