It is a thin and light book cover like paper. (Paperback size + thickness adjustable) Vegetable Tannin Tanning Kip (Veal) We use top quality materials that have been subjected to WAX processing to the utmost limit, thin to the limit. By using it for a long time, leather will change moistly, so I would like to enjoy the feeling more familiar to my hands. By making three belts to fix the book, It integrates with the book and fits as if it sucks more. And, while holding a bookmark, "How far were you reading on the way?" Is not such a thing? Since fixed bookmarks are attached to each side one by one, By using the side of the end of the reading, it becomes easier to find the end of the reading, it starts to read the continuation smoothly, it becomes a small help, I really would like to have fun reading time with Skinny Book Cover.