Cadillac 2004 Seville Owner's Manual page 41

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 attachments to secure the restraints. Some
restraints also use another vehicle anchor to secure a
top tether strap (C).
In order to use the LATCH system in your vehicle, you
need a child restraint designed for that system.
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