I was surprised to learn just now that Pit Viper isn't actually owned by Luxottica.
However they have many models that made in China and Italy, which means they are manufactured by Luxottica. Apparently some of them are still made in the US, but I wasn't able to find which ones.
Normally when a company is manufacturing something domestically they proudly announce it, because it's a good selling point. But I didn't see pit viper doing that in my brief searches, so it's safe to assume they're all made by Luxottica.
Which means these knockoffs probably came out of the same factory, if not the exact same product line.
You weren't able to sell them? I used to have a successful side-hustle on eBay, but I never did try to sell sunglasses. It seemed like there was too much competition for that.
I think it's supposed to be a delineation of arm/hand, because there's the same thing at the leg/foot interface. Apparently wrists and ankles have a different color than the rest of you.