Ford 2013 F-650 Owner's Manual page 40

Many tether straps cannot be tightened if the tether strap is hooked to
the loop directly behind the child seat. To provide a tight tether strap:
A single loop can be used to route and anchor more than one child seat.
For example, the center loop can be used as a routing loop for a child
safety seat in the center rear seat and as an anchoring loop for child
seats installed in the outboard rear seats.
2013 F-650/750 (f67)
Owners Guide gf, 2nd Printing, March 2013
USA (fus)
Child Safety
1. Route the tether strap through
the loop directly behind the child
seat.
2. Attach the strap hook onto the
loop behind an adjacent seating
position.
3. Install the child safety seat tightly
using the vehicle belts. Follow the
instructions in this chapter.
4. Tighten the tether strap
according to the child seat
manufacturer's instructions.
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