2009 Vantage Roadster - found 3 of these in my trunk rolling around. They feel metal, have a threading on the inside and a torx screw in the top.

 

Those look to hold on the panel in the back of the trunk. I've got six on mine (2 towards the front of the cabin on angled surface and 4 on the vertical surface). I've never take off the panel and not sure what is behind it.

 

these are for tie downs in the trunk area. I have tie down net in my car

 

Hi...MRCW is correct. The pieces vibrate loose once in awhile..
If no net just leave out and put in a bag to save...but there should be six..
Good luck

 

You guys are the best, thanks!!

 

If you have the wind deflector they hold the storage bag to the trunk panel.

 

Here is another one for you... found in my trunk rolling around. I have 2 of them, appear to be a metal plate, with 2 screws.

 

Those are the hold downs for the battery.

 

#Perfect. Original owner had it replaced but these were just sitting in the trunk. I just installed a new battery myself, but wasnt sure what the hell they are. Anyone have a picture so I know how the hell to put them back? The battery I have now had a large black metal strap with a screw underneath holding it down. And I also find it scary that I can see the ground when I look down there...

 

here's a pic

the net and attachment points