Mitsubishi Outlander 2007 Owner's Manual page 102

Seat and seat belts
To remove
To remove the head restraints, lift the head restraint with the
height adjusting knob (A) pushed in.
2
Installation
To install the head restraints, first confirm that they are facing
the correct direction, and then insert them into the seatback
while pressing the height adjusting knob (A) in the direction
indicated by the arrows.
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