Join the craze that's sweeping the nation! ColorKu is SUDOKU in COLOR! ColorKu also allows you to solve any SUDOKU puzzle using color! ColorKu start with one of the 104 puzzle cards, then get one of each color in every row, in every column, and in every 3 x 3 box. Quality wood playing board 13.5 " x 13.5 " with 81 wood marbles in 9 spectacular colors. Comes with clear high impact plastic bubbled storage tray, color conversion card, over 100 puzzle cards in four levels of difficulty, and a solutions booklet.