Chevrolet 2003 Avalanche Owner's Manual page 153

To use the storage bag, do the following:
4. Stow the cover using the buckles and the straps
attached to the front rail.
You can also store the tonneau cover outside of the
vehicle or use the storage bag included.
1. Attach the bag to the cargo tie downs as shown.
Unzip the top of the storage bag so it will be
ready when you need to stow the tonneau cover.
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