I home school my daughter so I am always looking for ways to keep our supplies organized. I bought this set of 8 large Book Binder Rings and I was not disappointed. The set comes with 8 nickel plated metal rings which are 2 3/4 inches in diameter and made of iron so they are super durable. I use this set to help keep my daughter's daily work together so that it is easy for her to know exactly what she needs to work on for each subject. I also use them to hang scarves up in my closet. My husband wants a set of the larger rings to use in his workshop for various organizing tasks. I have already ordered a second set for him. These rings have tons of uses.