Color: Silver; Material: Steel; Size: 20 x 16 x 2mm / 0.79 x 0.63 x 0.08 inch;24 x 19 x 2.2mm / 0.94 x 0.75 x 0.09 inch;30 x 25 x 2.4mm / 1.18 x 0.98 x 0.09 inch;38 x 31 x 2.8mm / 1.5 x 1.22 x 0.11 inch;50 x 44 x 2.9mm / 1.97 x 1.73 x 0.11 inch(OD*ID*T)||Advantage: The clip ring is a buckle design, which is secure and can be firmly fixed and not easily dropped. No matter what age you are, you can easily operate the loose-leaf ring, easy to open and easy to buckle. The creative book binder ring is strong and durable, not easy to be brittle, not easy to rust.||Instruction: Gentle firm outward pull from both sides. Pass the card rings through the hole in the paper and press the buckle.||Application: The loose-leaf ring holds the paper by a ring on the paper. Book rings can be used for loose-leaf books, memo filing, key rings, DIY scrapbooking, sample holders, organizing documents, index cards, flash cards, photo album, or other loose-leaf items. O rings can also be used as creative hangers, tie storage, curtain shower, and curtain hook. Binder rings are suitable for classroom, office, home, arts and crafts.||Note: Please select the appropriate size according to the size of the hole.