Hummer 2004 H2 Owner's Manual page 56

Lower Anchorages and Top Tethers
for Children (LATCH System)
Third Row Seat
Your vehicle has the LATCH system. You will find
anchors (A) in the center and right side passenger
second row seating positions.
This system, designed to make installation of child
restraints easier, does not use the vehicle's safety belts.
Instead, it uses vehicle anchors (A, B) and child
restraint attachements to secure the restraints. Some
restraints also use another vehicle anchor to secure
a top tether strap (C).
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