★ The 2021 Sudoku Calendar Puzzle Book This book is a new collection of Sudoku Puzzles for each day of the year! Puzzle difficulty varies for each day of the year ensuring you get a daily challenge. This daily sudoku puzzle book for 2021 will keep your mind active. - Size 8,5"x11" - New sudoku puzzle for each day of the year (365 puzzles) - Date & Difficulty shown on each puzzle - Give you endless fun and brain power training - Great gift for family, friends or work colleagues Improve logic skills and have fun today!