Welcome to our store! 1,[High Capacity] The plastic spiral binding coil has a diameter of 38mm and can hold up to 310 sheets of paper (A4, 70g), making it easy to add and remove pages. 2,[4:1 Pitch Compatibility] The spiral binding coil has a 4:1 pitch, making it compatible with all binding machines that punch 4 holes per inch. 3,[360 Degree Rotation] With the ability to rotate 360 degrees, this binding coil allows for easy page turning and reading, making it easier to work with bound projects. 4,[18 Pcs Set] Each package contains 18 spiral binding coils, ensuring long-term productivity for all your binding projects, allowing you to easily bind papers and store them securely. 5,[Versatile Application] Ideal for letter-size paper (8.5 x 11 inches), the length of the spiral coil can be easily cut with scissors. Perfect for technical documents, business projects, office documents, and university presentations. Item Type: Spiral Binding Coil Material: PVC Plastic Binding Diameter: Approx. 38mm or 1 1 or 2in Binding Capacity: 310 Sheets (A4, 70g) Number of Loops: 48 Pitch: 4:1 18 x Spiral Binding Coil Customers are our top priority. If you find any problems with your product after receiving it, such as damage or incorrect quantity, please contact us immediately. We strive to provide you with the best after-sales service.