There are 12 pcs lace shape book dividers per pack, and the large size of 6x12 inches is suitable for book classification in school or classroom library. Features: 6 kinds of classroom library book dividers are easy to use, just insert Plastic Shelf Marker Flexible next to the bookshelf, and then paste the matching stickers to fill in the book information. High-quality heavy plastic structure, thick design, not easy to bend, lace design will not hurt your hands. Each pack contains 24 repositionable stickers, you can DIY write down the necessary information, delete the date, author's name, favorites, etc. Usage: Use these double-sided book marker dividers to organize bookshelves by book category, author, or collector's edition book.Tab dividers are easy to quickly identify or find various themed areas of the shelf.