GMC 2007 Acadia Owner's Manual page 44

Third Row Center
Position
44
For the third row center
position, locate the
comfort guide which is
located in a storage
pocket, at the top of the
seat, under the
headrest on the driver's
side of the vehicle.
To access the comfort guide, you will first
need to move the headrest forward by pulling
on the handle behind the seatback. The
comfort guide will now be accessible. Pull the
comfort guide out of its storage location
and then return the headrest to its upright
position.
The elastic cord on the comfort guide is
adjustable. You can make it longer or shorter
by squeezing the both ends of the plastic
adjuster.