Sudokus are the ever-popular number placement puzzles that give your brain a workout. Spanning a number of difficulty levels, this collection is presented with beautiful, infinity edge designs, making it a perfect gift for any puzzle lover. - INFINITY EDGES: Features striking 'infinity' printed page edges - EXERCISE YOUR BRAIN: Give your mind a great workout as you pit your wits against these number-placement teasers. - REDUCE STRESS: Feel your stress melt away as you focus on these satisfying puzzles. - POCKET-SIZED: This handy layout is perfect for carrying on your travels or just to keep by your bedside.