This is a "Kurutto Ring" mini-size binder and loose-leaf set from Maruman Co., Ltd. You can combine the cover and rings to create a notebook to your liking. It can be folded back 360 degrees for compact use, and the rings are made of impact-resistant polycarbonate material. The binder can be easily opened and closed by pressing both ends of the ring while pulling the cover, but it has a two-stage structure to prevent it from accidentally opening in your bag. System notebook refill set, including check patterns and grid pages. - Set Contents: Green check refill, gray refill, black refill, white refill - Page Type: Grid pages - Refill Material: Plastic - Number of Holes: 6 holes Thank you for viewing.