appendix; supplement; bonus insert
Refers to supplementary material attached to a book, magazine, or newspaper, such as a booklet, poster, or CD. Can also mean a bonus item included with a publication.
This magazine comes with a special supplement every issue.
巻末に用語解説の付録がある。
There is an appendix with a glossary at the end of the book.
This month's magazine comes with a cute pouch as a bonus.
The publisher included a lavish bonus item to boost sales.
I bought that magazine mainly for the bonus item.