by Aguyfromohio » Mon Feb 12, 2018 11:13 am
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First an important disclaimer: I do not know. I really don't have any actual facts here.
Next, some fun speculation: It sure looks to me like a custom molded one-piece ring, it seems to change cross section and take the sharp turns without distortion. If it was standard catalog stock from somewhere I would expect a constant cross section. My guess is that they shoot it as chopped fiberglass with gel coat, or perhaps compression mold it from sheet molding compound.