Lexus GX470 2004 Owner's Manual page 220

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1 Anchor brackets 2 Symbol mark
Use the anchor brackets on the back of the second seatback
to attach the top strap.
Anchor brackets are installed for each second seating
positions.
This symbol mark indicates the location of the anchor brackets.
OCCUPANT RESTRAINT SYSTEMS
1. Remove the head restraint.
2. Open the cover of the anchor bracket.
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