Easy to read. Each puzzle has only 1 solution. 250 puzzles of silver level. Wide inner edges allow recording of solution options. Ideal gift for all fans of puzzles. Sudoku 6x6, separated by smaller rectangles of 3x2 cells. It is necessary to fill empty cells with numbers from 1 to 6, each of the digits should appear only once in each line of the 6 x 6 square, 6 x 6 column and 3x2 rectangle. Contains key numbers located along the sides of Sudoku. It is necessary to arrange the numbers in cells; each figure indicates the number of floors in a skyscraper. Key numbers outside the cells show how many houses can be seen in the corresponding row or column, if viewed from this number. In this Sudoku the same numbers can not "beat" each other with the chess steed. Excellent purchase for fans of Sudoku. A great book for relaxing in your spare time. There are 148 pages. The format is 6 '' x 9 ''. I hope you enjoy my book. I would also be very grateful if you could write a review. Thank you. Best regards, Andrii Pitenko