Most external frames have screws and snaps that affix the fabric to the frame. To remove the pack, simply unfasten the screws (you can do this by hand). Most packs have about 6 to 8 screws on each side, so it should be relatively easy. Removing the pack is also a great option to have because if your backpack is ever mauled by a bear, you don’t have to spend the extra money to buy a whole new backpack, because you still have the original external frame, and you can just buy a new pack which will be significantly less.