The Naval Aviation Guide -

UsedAcceptable. The item is very worn but continues to work perfectly. Signs of wear can include aesthetic issues such as scratches, dents, worn and creased covers, folded page corners and minor liquid stains. All pages and the cover are intact, but the dust cover may be missing. Pages may include moderate to heavy amount of notes and highlighting, but the text is not obscured or unreadable. Page edges may have foxing (age related spots and browning). May NOT include discs, access code or other supplemental materials.