Chevrolet 2008 Malibu Owner's Manual page 32

There is one guide for each outboard passenger
position in the rear seat. Here is how to install a comfort
guide to the safety belt:
1. Pull the elastic cord out from between the edge of
the seatback and the interior body to remove the
guide from its storage clip.
1-28
2. Place the guide over the belt and insert the
two edges of the belt into the slots of the guide.