Lexus ES-300 2001 Manual page 162

COMFORT ADJUSTMENT
To connect the extender to the seat belt, insert the
tab into the seat belt buckle so that the "PRESS"
signs on the buckle release buttons of the extender
and the seat belt are both facing outward as shown.
You will hear a click when the tab locks into the buckle.
When releasing the seat belt, press on the buckle
release button on the extender, not on the seat belt. This
helps prevent damage to the vehicle interior and
extender itself.
When not in use, remove the extender and store in the
vehicle for future use.
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