Feature:1. Size and Capacity: The spiral binding coil has a diameter of 16mm (5 or 8in), can accommodate up to 140 sheets of paper (A4, 70g), making it easy to add and reduce paper.2. Coil Specifications: These spiral binding spines are single wire and 48 loops design, with 4:1 pitch, which is compatible with any binding machine with 4 holes per inch.3. Durable Material: These single wire binding coils are made of excellent metal material, sturdy and durable, allowing you to easily bind paper and store it for a long time.4. Convenient Use: These paper binding spines support 360 degree page turning function, making your binding items flat and easy to read, improving work efficiency.5. Applicable Range: Includes 100 spiral binding coils, suitable for 8.5x11 inch paper, can be cut according to needs, used for binding engineering documents, office files, etc.Specification:Item Type: Spiral Binding SpinesBinding Diameter: 16mm (5 or 8in)Binding Capacity: 140 Sheets (A4, 70g)Number of Loops: 48 LoopsRatio: 4:1.Package List:100 x Spiral Binding Spines