I purchased two of these for my Spellbinders Nestabilities sets. I was able to fit 5 sets in each with room for 2-3 more in one of the binders. The binders are heavy, thin, and the flat the closes up the binder is secure. The binder comes packaged with a thick piece of solid cardboard that is going to be perfect to make a book with my new Zutter Bind-it-All (hey, you gotta recycle!) As my nesties collection grows, I am sure I will purchase more of these! The only negative I have about these is that I wish I could find the white ones and I wish there was a way to label the contents.