Cavity sealant

2). An automotive floor pan extension comprising an injection molded component having at least one integrally molded locking feature and wherein at least one sealant contacts at least a portion of the injection molded component.

3) A sealed region comprising at least three metallic automotive members at least partially in contact with a cavity sealer, wherein said cavity sealer comprises a molded component having at least locking feature, and wherein at least one heat activated sealant contacts at least a portion of said cavity sealer and said at least three metallic automotive members.

4). The sealant of claim 1 wherein said fastening feature comprises at least one weldable metal.

5). The sealant of claim 1 wherein said fastening feature comprises at least one self-locking tab.

6). The automotive floor pan extension of claim 2 wherein said sealant comprises a heat activated and expandable sealant.

7). The sealed region of claim 3 wherein one of said at least three automotive components comprises a floor pan.

8). The sealant of claim 1 wherein said tub comprises polyethylene terephthalate.

9). The automotive floor pan extension of claim 2 wherein the injection molded component comprises a fiber reinforced thermoset composite.

10). The sealed region of claim 3 wherein said molded component comprises injection moldable polyproplyene.

11). The sealed region of claim 3 wherein said at least one locking feature engages opening defined in at least one of said at least three metallic automotive members.