These 4-inch binder rings are way more useful than I expected! You get 15 of them in the pack, which is perfect because I always seem to need various sizes for different projects. The nickel-plated steel construction feels really durable - they have a nice weight to them without being too heavy, and the plating prevents rust and keeps them looking shiny. The 4-inch size (with about 4.3-inch outer diameter) is surprisingly versatile - big enough to hold multiple documents, photos, or craft materials but not so huge that they're awkward to use. The open-and-close mechanism works smoothly - you just pull to open and squeeze to close, and they lock securely so whatever you're organizing stays put. I've used these for so many things beyond just paperwork: as curtain rings for a DIY project, as large key rings for organizing keys, for holding together fabric samples, even for creating custom photo albums. They're sturdy enough that they don't bend out of shape with use, which is a problem I've had with cheaper binder rings. For the price, getting 15 quality rings is an absolute steal compared to office supply stores. If you're someone who likes to stay organized or enjoys DIY projects, these binder rings are definitely worth having on hand.