It's made of a Polyethylene blend (grills are ABS, an entirely different material with different properties). Problem is that the Polyethylene/Polypropylene family of plastics are very "slick" and HIGHLY chemical resistant (they make containers for acids, paint stripper, etc. from a similar material due this fact). So, it's rather like gluing a broken candle together, glues, fiberglass and such don't adhere to it well, they just sit on top and eventually peel off. Therefore, pretty much impossible to "glue it" with anything. When they make repairs to large industrial containers they use heat and weld it together but this leaves visual melted plastic scaring which don't look good on our car parts. If you have light scratches or cosmetic imperfections you can use plastic epoxies as a filler and finish paint the shroud black with SEMS interior paint and get a nice finish, but as you know, O.E. correct is bare plastic.

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