Ford 2006 F150 Owner's Manual page 158

Seating and Safety Restraints
Attaching child safety seats with tether straps
Most new forward-facing child safety seats include a tether strap which
goes over the back of the seat and hooks to an anchoring point. Tether
straps are available as an accessory for many older safety seats. Contact
the manufacturer of your child seat for information about ordering a
tether strap.
The passenger seats of your vehicle are equipped with built-in tether
strap anchors located behind the seats as described below.
The tether anchors in your vehicle may be loops of webbing above the
seatback or an anchor bracket behind the seat on the rear edge of the
seat cushion.
The rear seat in the SuperCab and SuperCrew has three straps along the
top of the seatback that function as both routing loops for the tether
straps and anchor loops.
The tether strap anchors in your vehicle are in the following positions
(shown from top view):
Attach the tether strap only to the appropriate tether anchor as
shown. The tether strap may not work properly if attached
somewhere other than the correct tether anchor.
• F150 Regular Cab
• F150 SuperCrew and SuperCab
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