GMC 2010 Yukon XL Denali Owner's Manual page 93

Your child restraint may have a single tether (A) or a
dual tether (C). Either will have a single attachment (B)
to secure the top tether to the anchor.
Some child restraints with top tethers are designed for
use with or without the top tether being attached. Others
require the top tether always to be attached. In Canada,
the law requires that forward-facing child restraints have
a top tether, and that the tether be attached. Be sure to
read and follow the instructions for your child restraint.
If the child restraint does not have a top tether, one can
be obtained, in kit form, for many child restraints. Ask
the child restraint manufacturer whether or not a kit is
available.
Lower Anchor and Top Tether Anchor
Locations
Second Row 60/40
Second Row Bucket
(Lower Anchor):
Seating positions with
two lower anchors.
(Top Tether Anchor):
Seating positions with
top tether anchors.
(Lower Anchor):
Seating positions with
two lower anchors.
(Top Tether Anchor):
Seating positions with
top tether anchors.
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