binding coils
5 Sizes Assorted for Different Sheet Capacities： This 50 pack spiral binding coils kit includes 5 popular diameters: 1/4", 5/16", 3/8", 1/2", and 3/4" (6mm, 8mm, 10mm, 12mm, 20mm). Each size holds different sheet counts, making it easy to choose the right coil binding spine for your document thickness.
Standard 4:1 Pitch for Wide Compatibility： Designed with standard 4:1 pitch spacing (4 holes per inch), these spiral binder coils are compatible with most coil binding machines and pre-punched papers for smooth, secure binding.
Strong & Flexible Plastic Binding Coils： Made from high-quality plastic, these spiral binding coils are flexible yet sturdy, allowing pages to turn 360°without cracking or deforming. Ideal for reports, presentations, notebooks, and manuals.
Organized Mixed Set – 10 Coils per Size： Each diameter includes 10 pieces, giving you a well-balanced assortment for office, school, or print use. No need to purchase multiple packs separately.
Clean Black Finish for Professional Look： Classic black spiral coils provide a neat and professional appearance, suitable for business documents, proposals, workbooks, planners, and personal projects.