I could never figure out what that slide thing that attaches to the tunnel is for, but I would bet money it doesn't save your life in an accident. The substantial part of the buckle is mounted to the seat frame itself, which is in turn bolted to the floor. If you ever took the seat out (like I have), you would realize that the thin piece of metal that bolts to the tunnel merely slides back and forth in the buckle bracket. There is no lock mechanism on that piece of metal that I could see that would transfer force, so I maintain that most of the force is going through the frame of the seat itself. Hence, my concern about installing a non-OEM seat.