Join Date: Jun 2006
Location: Warrington, Cheshire, UK
I'm not entirely sure what you mean 'behind the headrest' but my understanding is this:
Your isofix seat has two connections at the bottom, both facing backwards. They attach to the isofix mountings through the gap between the seat back and the bench; you can do this on either side but not the middle.
Next the seat may have a top tether, which is like seat belt type material, attached to the back of the seat and with a metal clasp on the end. You put this over the top of the seat and then down into the boot where you'll find a connection (one on either side again) to attach it to.
That's it, I think - makes sense?