Pretty small, but with all the little advantages of a large pack. Just about every part of the pack is adjustable. Very solid fabrics used. Only thing that could be better is that the plastic sheet that gives the back panel its support could be stronger. I find that when I put articles in the top without filling the rest of the pack, the weight of the top pulls on the two top corners of the plastic backing and deforms it. Having the metal stay rod doesn't help because its in the middle. Maybe I should only put stuff in the top when I fill the rest of the bag. Anyway, great pack, with a pretty sweet design, as always, from Marmot.