GMC Envoy Owner's Manual page 32

4. Be sure that the belt is not twisted and it lies flat.
The elastic cord must be under the belt and the
guide on top.
5. Buckle, position and release the safety belt as
described in Rear Seat Passengers on page 1-21.
Make sure that the shoulder belt crosses the
shoulder.
To remove and store the comfort guides, squeeze the
belt edges together so that you can take them out of the
guides. Slide the guide back onto its storage clip or
into its storage pocket.
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