Fellowes 20mm silver-tone metal binding spirals with a 5:1 pitch (100 units) 5115801 ensure strength for binding very dense documents. Supplied in a box of 100 units with a 20mm diameter and 5:1 pitch, these silver metal spirals comfortably hold up to 170 A4 sheets. The shine of the silver tone enhances the perceived value of the presentation. Perfect for project files, academic theses, and corporate reports.