1、SPECIFICATIONS: Double wire binding spine, with 13mm binding diameter, 34 loops, and 3:1 ratio, can accommodate up to 120 sheets of paper (A4, 70g). 2、DOUBLE METAL WIRE: These binding coils are made of excellent metal wire, which is sturdy and durable, allowing you to easily bind paper and store it for a long time. 3、NYLON COATING: These binding spines have nylon coating on the outside, with good glossiness, corrosion resistance, wear resistance, and has a long service life. 4、MULTIPLE USES: These double wire spiral binding spines can be used for organizing documents, files, reports, etc., and compatible with most wire binding system. 5、100PCS IN 1 SET: Includes 100 pieces double wire binding coils, lightweight and compact, which are easy to use and replace, meeting various paper binding needs. 100 x Binding Coils Item Type: Spiral Binding SpinesBinding Diameter: 14.3mm (9/16in)Binding Capacity: 120 Sheets (A4, 70g)Number of Loops: 34 LoopsRatio: 3:1