1. Made of kraft paper material, it is tear resistant and easy to use. 2. With an outer diameter of 0.5 inches and an inner diameter of 0.25 inches, there are a total of 2500 pieces in one set, enough to meet your usage needs. 3. Easy to use, remove the middle hole to provide the necessary protection for your files. 4. Suitable for school, home education, library and office documents, loose leaf folders, calendars, etc. It is also an ideal choice for repairing or designing torn loose leaf paper, making labels, protecting address book pages, and making VBS crafts. 5. Self adhesive material, suitable for any flat surface.