yes they were plastic at least the few that ive seenwere one on a original hz gts and two sandman ones all plastic

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i bought one fiberglass spoiler off ebay cost 150 or thereabouts but i spent so much time filing down and moulding just to get it to fit right i could have bought 2 of these plastic ones, i wish i knew about these plastic ones earlier, in saying this all spoilers im sure will require some extra fitting from the factory and being that a great deal of fronts have been damaged /rusted and repaired of course they arnt going to fit strait up