Thank you for viewing! This item is made from a Starbucks craft paper bag that has been laminated on the surface, making it stiff and water-resistant. The width is adjustable for books, but for paperbacks, the height varies slightly, so this was made to fit the shorter ones (15.8mm). It will fit almost all paperbacks. It matches the pen case. Creases may occur during production, but this gives it the unique texture of a paper bag and makes it cute. How about using it as a companion for reading?