Graco NAUTILUS SNUGLOCK LX Instruction Manual page 77

9. Insert Metal Retainer in the
New Buckle Strap Slot
Reach underneath the car seat and pull the
metal retainer through.
10. Pull Up on Buckle Strap to Make
Sure it is Secured
11. Buckle the Chest Clip
You will hear a "click" when the chest clip
is securely buckled.
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