I would say it is defintely an aftermarket equivalent. I had a snugtop for a while for a street car, and comparing it to factory tops, the only difference I could find was the latches, which have to get removed anyway. Barring that, I personally couldn't find any differences, although I admit to not breaking out a tape measure and going to town on it.
Someone on one of the Pinata sites weighed one and it was actually heavier than a factory top by ~2-3lbs.
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