This a great bag and very strong. I wanted to give it 5 stars because the bag is big and has plenty of pockets. There aren't many urban style day packs over 30L and this is a good one, but the thread liner next to the zipper is too close to the zipper making the bag hard to open and close. It makes the zipper get caught. You have to open it very carefully or pull it fast and hope you don't rip the bag.