This is a stainless steel and enamel version of the world's best-selling puzzle that dates from the 19th century. It's still addictive and still the most portable travel game we can think of. To play, scramble the 15 numbered tiles in the tray, then try to slide them into correct numerical order. Includes an instruction book with more than 30 challenges and a leatherette travel pouch. 5" x 5"