Lap Belt (Crew And Extended Cab) - GMC Sierra 2008 Owner's Manual

The best way to protect the fetus is to protect the
mother. When a safety belt is worn properly, it is more
likely that the fetus will not be hurt in a crash. For
pregnant women, as for anyone, the key to making
safety belts effective is wearing them properly.

Lap Belt (Crew and Extended Cab)

This part is only for the lap belt. To learn how to wear a
lap-shoulder belt, see Lap-Shoulder Belt on page 1-28.
You vehicle may have a center seating position.
When you sit in the center front seating position,
you have a lap safety belt, which has no retractor.
1-34
To make the belt longer, tilt the latch plate and pull it
along the belt.