Wrapping is a binding form of ancient books in China. The pages are folded back to back, so that the printed side faces outward, and the page opening is used as the book opening. Then, stick the two sides of the page on the spine, twist the paper and bind it, and finally wrap the coat of the whole book on the back. Because the book mouth of Baobeizhuang is outward, it will wear the book mouth upright, so the books of Baobeizhuang are generally flat on the bookshelf.

The binding and use of books in Baobeizhuang is more convenient than butterfly binding, but the binding procedure is still more complicated, so it was quickly replaced by another binding form-thread binding.

Zhang Geng Fu said in The Origin of Book Binding in China: "Butterfly binding is beautiful, but the pages are like lines. If you turn it too much, it will eventually fall down. Baobeizhuang runs through the book and is much stronger. " In the Yuan Dynasty, Bao Bei costume replaced the butterfly costume.