Fold, the extension of the front cover and back cover of a book (the former is called "front fold" and the latter is called "back fold"), the width is generally ≥ 30 mm ..

The functions are as follows: posting the author's information (or writing purpose, or main content), protecting the book block (body part), beautiful, and signing * (for book sales) (some fans like to ask people to sign here).

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1. Flaps-Recommended

2. Jacket flip

Step 3: sleeves

Step 4 bind

See above for a similar expression.

. . .

put on file