Pontiac 2005 Montana Owner's Manual page 77

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CAUTION:
Using the vehicle's built-in child restraint as a
booster seat for a larger child could cause
injury to the child in a sudden stop or crash. A
child whose weight is over 40 pounds, whose
height is over 40 inches or whose shoulders
are above the shoulder belt slots for the
harness system should use a restraint system
that is appropriate for their size, either an
add-on booster seat or the vehicle's safety
belt. See "Child Restraints" or "Older
Children" in the Index.
Securing a Child in the Built-In
Child Restraint
1. Raise the head restraint until the lower edge of the
head restraint is even with the top of the seatback.
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