that looks thicker than 10 mm that's why i was questioning it.looks like 10mm coro, either UV printed, or mounted with vinyl.
i thought at first it might be foamboard. (I hate that stuff)When you really zoom in on it, you can see it appears to be a front piece of Cor-X and a back piece of Cor-X and doubled over for strength and down the back of the front piece a ways. Can't be 10mm or it wouldn't've creased like that so often. Also, looks like a direct print
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Right?This place is getting more painful by the day.