These 50pcs binding rings are made of high-quality plastic, durable flexible. The double buckle design allows for easy secure binding storage of loose leaf books, cards, other items. Available sizes are 15/20/28/40mm colors include pink, red, yellow, green, blue, multicolor. Keep your loose leaf items organized easily accessible with these practical useful binder rings. Features: 1. Made of high-quality plastic, flexible, high toughness, not easy to be broken, durable to use. 2. Practical useful tools can make your loose leaves organized. Suitable for binding storage of cards, loose-leaf books, etc. 3. Size: Inner Diameter: 15mm, 20mm, 28mm, 40mm optional. Double buckle design is stronger, easy to buckle not easy to loose. 4. Used for the loose-leaf books, key rings, notebooks, scrapbooking, or other loose-leaf items. 5. Package included: 50 x Loose Leaf Rings. Color: Pink, Red, Yellow, Green, Blue, Multicolor optional. Specification: Material: Plastic Color: Pink, Red, Yellow, Green, Blue, Multicolor Product Size: Inner Diameter: 15mm, 20mm, 28mm, 40mm Product Weight: 25g, 37g, 64g, 125g Package Included: 50 x DIY Binder Ring