what is this part?

its in the boot, was stuck on the top, got no idea what its used for?
any help?
http://www.pelicanparts.com/cgi-bin/sma ... PPORT%20RT
[img]http://www.pelicanparts.com/cgi-bin/smart/more_info.cgi?command=show_parts_image&BMW_Diagram=24612&BMW_Diagram_X=338&BMW_Diagram_Y=515&BMW_Diagram_POS=19[/img]
any help?
http://www.pelicanparts.com/cgi-bin/sma ... PPORT%20RT
[img]http://www.pelicanparts.com/cgi-bin/smart/more_info.cgi?command=show_parts_image&BMW_Diagram=24612&BMW_Diagram_X=338&BMW_Diagram_Y=515&BMW_Diagram_POS=19[/img]