GMC 2009 Sierra - Manual (Page 49)

{ CAUTION:
Each lower anchor and top tether anchor in the
vehicle is designed to hold only one child
restraint, except the center top tether anchor in
crew cab models. Attaching more than one
child restraint to a single anchor could cause
the anchor or attachment to come loose or
even break during a crash. A child or others
could be injured if this happens. To help
prevent injury to people and damage to your
vehicle, attach only one child restraint per
anchor.
{ CAUTION:
Children can be seriously injured or strangled
if a shoulder belt is wrapped around their neck
and the safety belt continues to tighten.
Secure any unused safety belts behind the
child restraint so children cannot reach them.
Pull the shoulder belt all the way out of the
retractor to set the lock, if your vehicle has
one, after the child restraint has been installed.
Be sure to follow the instructions of the child
restraint manufacturer.
Notice: Contact between the child restraint LATCH
attachment parts and the vehicle’s safety belt
assembly may cause damage to these parts. Make
sure when securing unused safety belts behind
the child restraint that there is no contact between
the child restraint LATCH attachment parts and
the vehicle’s safety belt assembly.
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