The short answer is that AA grade means lots of mahogany. The longer answer is contained on the page attached below from the 1914 Old Town catalog that describes the AA grade in more detail. You can get more information like this from the Complete Old Town Canoe Company Catalog Collection CD available at http://merchandise.wcha.org/ and http://www.dragonflycanoe.com/cdrom.htm on the web. Feel free to reply here if this doesn't answer your question.