Pontiac Vibe 2007 Owner's Manual page 55

If the position you are
using does not have a
head restraint and
you are using a dual
tether, route the
tether over the
seatback.
If the position you are
using has an adjustable
head restraint and
you are using a dual
tether, route the
tether around the head
restraint.
3. Push and pull the child restraint in different
directions to be sure it is secure.
If the position you are
using has an adjustable
head restraint and you
are using a single tether,
raise the head restraint
and route the tether
under the head restraint
and in between the head
restraint posts.
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