<ul><li>Over 100,000 puzzles</li><li>Three difficulty levels plus hint and puzzle checker</li><li>Built-in timer</li><li>Choose from either 6 x 6 or 9 x 9 playing boards</li><li>Challenge yourself with the ultimate puzzle - Sudoku</li></ul><br><br>From the Manufacturer\n\nChallenge yourself with the ultimate puzzle - Sudoku. This electronic version features thousands of puzzles, doodle features, undo and hint buttons. There are three difficulty levels and a timer for challenging play. Choose from 6 x 6 and 9 x 9 playing boards. Requires two AAA batteries which is included.