GMC 2004 Canyon - Manual (Page 49)

Anchor the top strap to one of the following anchor
points. Be sure to use an anchor point located on the
same side of the vehicle as the seating position
where the child restraint will be placed. If you have an
adjustable head restraint, route the top strap over it.
When using a top strap-equipped child restraint in a rear
outboard seating position of a crew cab model, route
the top strap over the top of the seatback. Then, attach
it to the anchor point for that seating position.
{ CAUTION:
Each top tether bracket is designed to anchor
only one child restraint. Attaching more than
one child restraint to a single bracket could
cause the anchor 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 bracket.
Once you have the top strap anchored, you’ll be ready
to secure the child restraint itself. Tighten the top
strap when and as the child restraint manufacturer’s
instructions say.
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