FORD 2010 F-150 v.1 - Manual (Page 171)

WARNING: Safety belts and seats can become hot in a vehicle
that has been closed up in sunny weather; they could burn a
small child. Check seat covers and buckles before you place a child
anywhere near them.
WARNING: Front and rear seat occupants, including pregnant
women, should wear safety belts for optimum protection in an
accident.
Combination lap and shoulder belts
1. Insert the belt tongue into the
proper buckle (the buckle closest to
the direction the tongue is coming
from) until you hear a snap and feel
it latch. Make sure the tongue is
securely fastened in the buckle.
2. To unfasten, push the release
button and remove the tongue from
the buckle.
Seating and Safety Restraints
171
2010 F-150 (f12)
Owners Guide, 1st Printing
USA (fus)