Not 100% sure on this, but I understand they just push into the seat back and 'click' into place..........mine came adrift years ago when car was only about a year old, happen I caught if funny, it moved away from the seat back and collapsed into a vertical position. Took it to the dealer, they just corrected the position, and pushed it home until it 'clicked' into place.............hope that helps, though like not 100% .....Cheers Qube O.