Hummer H2 2009 Owner's Manual page 13

CAUTION: (Continued)
The lap belt cannot do its job either. In a crash the
belt could go up over your abdomen. The belt
forces would be there, not at your pelvic bones.
This could cause serious internal injuries.
For proper protection when the vehicle is in
motion, have the seatback upright. Then sit well
back in the seat and wear your safety belt
properly.
Do not have a seatback reclined if the vehicle is
moving.
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