Size2 inch / 50 mm diameter (outer ring), hold up to 450 sheets of 20 lb paper, 25 pieces Loose Leaf Binder Rings High QualityThe book loose leaf rings are made of iron material, strong and durable, Multi-layer nickel-plated steel rings prevent Easy to OperateConvenient to use just pull to open and squeeze to close; the misalignment occurred after opening, because the binder ring itself did not use spring or other elastic devices, in order to make the bite tightness after closing more tightly, so this design was used Wide ApplicationUse these convenient rings to bind documents, or to link together a multitude of different materials, Great for loose-leaf, memo filing, key rings, scrapbook, binding recipe, photos, book, sample book, scrapbook, contract or file