Belt seal with pen holder, convenient for planners and notebooks. - Product Name: Belt Seal Snap - Application: For planners, notebooks, and files - Pen Size: Compatible with pens up to 13mm in diameter - Made in: Japan - Materials: PP resin, PET Thank you for viewing. I think it can be used with Hobonichi Techo, etc. There are three available. If you want two or more, I will deduct the shipping cost.