Unused. It has been stored at home. Due to shipping costs, double packaging may not be possible. In such cases, for example, it may be sent directly in an envelope. This is a problem book that covers all six years of elementary school math, allowing you to learn from the basics to advanced concepts. - Title: Problem Book to Thoroughly Understand 6 Years of Elementary School Math in One Book - Publisher: Gakken Plus Co., Ltd. - Revised Edition: Revised Edition - Publication Date: January 19, 2020 - ISBN: 978-4-05-204700-2 Thank you for looking.