GM Chevrolet Avalanche - Manual (Page 134)

5. Remove cargo panel 1 (if you need to), but notice
that there are four latches to release (two left-side
latches and two right-side latches). Set the
panel aside.
After you have removed each cargo panel you can store
it within the cargo storage area using the cargo panel
storage system.
Cargo Panel Storage System
The three cargo panels can be stored on either the
driver’s or passenger’s side of the cargo box using the
storage bag. To store the panels, do the following:
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