Sudokus are the ever-popular number placements puzzles that give your brain a workout. Spanning a number of difficulty levels, this collection comes in an elegantly designed package with an elastic strap, making it the perfect gift for yourself or others.? 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.? GIFT EDITION: Designed with a stylish cover, this collection would make a brilliant gift for all puzzle-lovers.