2003 Chevrolet Avalanche Owner's Manual - Page 150

Top-Box Storage Tonneau Cover properly stored tonneau cover components could be thrown about the vehicle during a collision or sudden maneuver. You or others could be injured. If you remove the cover, bows and rails, always store them properly in the cargo area. When you put them back, always be sure that they are securely reattached. Your vehicle is equipped with top-box storage units on both side of the vehicle. The passenger sidetop box will contains the tools you need to change a flat tire. Use the ignition/door key to unlock the top box lid if it is locked. Press the key cylinder button and swing the lid open. Turn on the cargo lamps if you need more light inside the Top Boxes. See "Cargo Lamps" under Exterior Lamps on page 3-13 for more information on cargo lamps. Use the ignitioddoor key to lock the top boxes. 2-77