In the diagram, which one is the cat??

I have gotten conflicting info, some saying that the cats are only under the hood, and some saying that the cat is the long thing a 1/3 of the way back on the car...

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-Justin

91 560 SEC AMG - other dogs dd
01 Honda S2000 - dogs dd
07 MB ML320 CDI - dd
16 Lexus IS250 - wifes dd

it's automatic.