GMC Cadillac XT4 2019 Owner's Manual page 73

72 SEATS AND RESTRAINTS
this applies force to the strong
pelvic bones and you would be
less likely to slide under the lap
belt. If you slid under it, the belt
would apply force on your
abdomen. This could cause serious
or even fatal injuries.
Wear the shoulder belt over the
shoulder and across the chest.
These parts of the body are best
able to take belt restraining forces.
The shoulder belt locks if there is
a sudden stop or crash.
Warning
You can be seriously injured,
or even killed, by not wearing your
seat belt properly.
Never allow the lap or shoulder belt to
become loose or twisted.
Never wear the shoulder belt under
both arms or behind your back.