portland_bill said:

Firstly, are you sure it came from your car? Could it have been there before you arrived? Just because you've just noticed it, doesn't mean it has just arrived.

It looks like a buffer. So, suspension, or exhaust.
Looking on ePER, the parts listing:
The exhaust does not appear to have any extra buffer, only the normal rubber hangers.
The suspension bumpstop in the centre of the spring does appear to have a pointy top. Check both sides for a comparison.
Other than that, crawl underneath with a torch and look for any hole with a clean edge, looking like it is missing something. Pay particular attention to anywhere where moving parts could touch, so near suspension and exhaust.

When you find its home, please post a new pic of it in place.

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SPORTPACK50 said:

I'm the lucky owner of a 2007 100HP.
After spending a few happy hours under the rear of the car trying to separate the back box from the centre pipe section, I came across this part lying on the ground underneath where I was working!!
Anybody know what it is and where it should be!

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varesecrazy said:

Rubbery..??
and around 19mm in diameter..

Strange. Suspension rubbers will be bigger diameter

Dous the flat end have signs of glue or rust..? Or even look torn / sheared off.

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