Graco NAUTILUS SNUGLOCK LX Instruction Manual page 45

11B. Attach Top Tether Strap
Extend the top tether by
pressing the grey button
and pulling out on the strap
and attach.
Consult vehicle's owner manual for specific
location.
12B. Tighten Top Tether Strap
Remove all the slack.
13B. Test For Tightness
Grab the sides of the seat where the UAS
strap is and slide the car seat side-to-side
and front-to-back.
If the seat moves less than 2.5 cm (1"), it is
tight enough.
See section 5-A to secure your child.
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