I bought a Nissan, 05 King Cab, in the back seat there were two loose plastic items, one kind of looks like sort of a angled piece with a flat bottom and some spots that look like they may be drilled or attached to something. It's not a box i don't think b/c the under the seat, the box is attached on the rear driver's side. Nothings attached under the other seat, so maybe it goes there and serves some purpose? The other piece is a small slotted wedge shaped piece, maybe a seat belt attachment? They both are Nissan plastic w/ the Nissan logos on them. Any thoughts?