I was going on a trip to Macchu Pichu and the Galapagos that involved a lot of hiking, and wanted a lightweight backpack that didn't take up much room in my suitcase. This Marmot Kompressor Pack was PERFECT! It weighs less than one pound and folds up into itself converting into a little zippered pouch, so takes up hardly any room and adds hardly any weight to your suitcase. It holds an amazing amount of stuff. Since it is a toploader, it can hold things that are pretty large (e.g., it held my collapsible walking sticks just fine, along with a bunch of other things). The Kompressor straps are very useful to make the bag smaller when it is either not full, or is filled with soft things (clothing, towels) that cna be compressed. It has a strap that buckles across the front so that the bag is on tight and doesn't move around or slip off as you hike or climb. It has a zipper pouch in the top to put small things so you don't have to dig around for them in the main compartment (money, ID, sunscreen, sunglasses, etc. -- it holds quite a bit). The straps are very comfortable. The final plus is that it has a removable stiff but thin foam piece that (a) adds form to the pack if desired, (b) can be removed to sit on e.g. if the area is wet or dirty, (c) can roll up into the zipper pouch, or (d) can be totally removed to reduce the overall weight of the bag. I like this backpack so much that I purchased one for my brother and his wife to use when they travel. HIghly recommended!