I homeschool my kids and I have used these to keep their note cards together. I have them divided and sorted by different things and with the amount of rings you get, it's worth it. So far the cards have stayed together and none of the rings have opened up. We have thrown them in bags and they have held up nice. I have about 45 cards on each ring and there is still more room. So far I fee like these are really strong rings and they seem to be holding up pretty well. For the price you can't beat it. You get so many in one pack. After I bought these I went back and read that they can hold up 450 pieces of paper, which is very impressive. I have used a few of these to put spare house keys on for the kids since they are very durable and they do not come apart.