The product is a lot of 12 hardcover books from the "Diary of a Wimpy Kid" series by Jeff Kinney. These books are intended for children and young adults, with a focus on adventure and humor. 

See photos for book titles. If you are collecting the series, these are books 1 through 10, 13 and 14.

I have many more children/young adult book series on my ebay page, please check it out if interested.