From the manufacturer:
Take fun on the go with this "re-markable" take-anywhere book of dry-erase marker spy games! Choose from 16 different wordplay, creative, and picture spy and detective games for one or two players, including classics like mazes and I-spy, as well as games that are sure to become new favorite challenges, like code-breaking and Crazy Car Chase. Two included dry-erase markers with built-in eraser caps store conveniently in the cover of the spiral-bound book, making it a perfect travel activity for kids six and older. It's easy to write on, erase, then play again!