staples 923050 arc system 1-inch notebook expansion discs black 12/pack (20773) staples increase writing or storage space with this 12-pack of staples arc system 1-inch black notebook rings. add extra pages for writing or storing images, planner sheets and accessories with these black notebook rings. the smooth discs prevent torn paper, and interchangeable rings let you remove, add or re-arrange pages to organize information quickly or customize personal planners and journals. the 1-inch expansion of these staples notebook rings contains 60 sheets and provides extra space as needed without switching notebooks. notebook expansion disc allows you to add, remove and replace pages easily; the expansion disc is interchangeable to create more storage space. disk dimension: 1". comes in a sleek black design. 12 expansion disks per pack. staples brand 100% satisfaction guaranteed.