This style is called “Japanese Binding.” The spacing can vary in distance at the spine. The long line colours can be numerous. It’s durable. It is distinctive. If somebody wants a hardback case bound book, we simply bind the book in as indicated. Full surface glue the back cover inside the back panel of the case. When the book is opened the cover spine falls off. The sewing is exposed. It’s permanent. You can’t add or subtract sheets. It does not lay very flat at all.