Toyota 2009 Tundra Owner's Manual page 166

Forward facing ⎯ Convertible seat
Booster seat
Selecting an appropriate child restraint system
n
Use a child restraint system appropriate for the child until the child
l
becomes large enough to properly wear the vehicle's seat belts.
If a child is too large for a child restraint system, sit the child on a rear
l
seat and use the vehicle's seat belt. (→P. 75)
1-7. Safety information
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