Get your brain active with this Active Brain Series 2 book containing 400 gigantic sized puzzles, 200 medium and 200 hard, two different levels of difficulty to help increase your ability. Each huge puzzle fills the whole letter size page leaving plenty of space for penciling in the possibilities. Just one puzzle per page and solutions at the end of the book. Sudoku is a fun way to exercise your brain and there are plenty of puzzles in this book to give it a really good workout! 8.5" X 11"