As I was piecing my trunk back together, I found this hiding under by the Bose amp. I don't think it came off anything in the trunk. Funny thing is, it still has the adhesive backing untouched and unpeeled.
I'm guessing the previous owner bought it and never installed it.

Any ideas what it's for?

 

So it looks like this, with another piece that I found, are for removing them arm rest and making it look factory. Very weird. Did everyone else's car come with this?

 

Yeah, it is included with the car.