The puzzles are packaged in a handy and pretty format, which is perfect for taking with you for puzzling wherever you go. Each puzzle is graded, from beginner to expert, so you can enjoy the satisfaction of seeing your skill improve as you work through the levels. Give your mind a great workout as you find where each missing number fits. Feel your stress melt away as you focus on these satisfying puzzles. This handy layout is perfect for your travels, pocket or bag, or just to keep by your bedside.