The Fifteen Puzzle is a beautiful stainless steel sliding-tile puzzle. Enameled number tiles (from 1 to 15) are arranged in rows and columns of four on a 2.5 by 2.5 inch square frame. The empty space allows you to easily slide the tiles around on the puzzle. Unlike plastic versions, these tiles won't fall off! The premise of the game is simple. On a piece of paper, arrange the numbers 1 through 15 in any pattern in a four by four array. Then, see if you can reproduce the arrangement on the puzzle. To get you started, 30 puzzle challenges are included. Trillions of combinations are possible. The puzzle comes with its own travel case and provides fun for ages 8+