2003 Hummer H2 Owner's Manual - Page 64

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. Raise the head restraint and route the top strap under it. 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. A child restraint with a top strap should only be used in the second or third row. Don't use a child restraint with a top strap in the front seat because there's no place to anchor the top strap. An anchor loop bracket for a top strap is located at the bottom rear of the seat cushion for each seating position in the second row, and for the right outside seating position in the third row. Second Row Seats 1-58