Hummer H2 2009 Owner's Manual page 6

Head Restraints
The front seats have adjustable head restraints in the
outboard seating positions.
CAUTION:
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With head restraints that are not installed and
adjusted properly, there is a greater chance that
occupants will suffer a neck/spinal injury in a
crash. Do not drive until the head restraints for all
occupants are installed and adjusted properly.
1-2
Adjust the head restraint so that the top of the restraint
is at the same height as the top of the occupant's head.
This position reduces the chance of a neck injury in a
crash.