Item Type: Binding Spine_x000D_Inner Diameter: Approx. 12mm / 0.47in_x000D_Number of Holes: 34 Holes_x000D_Binding Pages: 12mm 85 sheets (for reference) 1SPECIFICATIONS: This plastic binding spine is a 34 hole design with an inner diameter of 12mm, which can bind about 85 sheets of paper (for reference). 2PLASTIC MATERIAL: Made of excellent plastic material, reusable and lightweight, which has good toughness, wear and aging resistance, and long service life. 3GOOD DURABILITY: These binding rings have good surface gloss, strong adhesion, not easy to break or fade, easily bind paper and store for a long time. 4EASY TO INSTALL: Just punch the appropriate holes in the paper for manual binding, suitable for office, school or home use, convenient and practical. 510PCS IN 1 SET: Including 10pcs binding loops, sufficient quantity for easy use and replacement, detachable split design, easy to open and close at any time.10 x Binding Spines