uxcell 20 Pcs Silver Tone Metal 1.1" Loose Leaf Bundle Book Rings Keyrings Outside Diameter : 29mm/ 1.1";Inside Diameter : 24mm/ 0.95";Thickness : 2.2mm/0.09" Wide range of uses such as loose-leaf, memo filing, key rings and sample holders. Closed tight, not scattered after collapse, a good organizer. You can easily link numerous loose-leaf booklets, paper cards, name tags, instruction guides or plastic plates together. The ring open and close easily, lock for extra security, easy to operate, pull to open and squeeze to close.