Features Practical binding method: can be manually connected by punching suitable holes, which can be easily used by any office, student party and individual. GOOD SHINE WITHOUT BREAKING: Has good surface gloss, strong adhesion, wear resistance, rust resistance, aging resistance, not easy to break and fade, smooth page turning, can be used repeatedly. 19MM INNER DIAMETER: Stationery accessories binding consumables, 19mm inner diameter, suitable for students and teachers. DURABLE WITH LONG LIFE - Durable and sturdy plastic binding spirals allow you to easily compile paper and store it for long periods. 20 pieces in total: The package contains a total of 20 binding spirals, enough for you to replace and use, very practical. Specification: Item Type: Plastic Spiral Binding Spools Inner diameter: approx. 19mm/0.75in Type: Stationery Accessories, Binding Consumables Package list: 20 x Plastic Spiral Binding Spools Package List 20 x Plastic Spiral Binding Coils