Miniature sudoku game which attaches to your keyring or wallet. This game is addictive! It will give hours of fun for the discerning maths whiz. Although it is small in size it makes up for it in entertainment. Fits neatly into the palm of your hand and needs only the lightest touch to activate the LCD screen and the numbers. -Four levels of difficulty -Includes a million games -Power: two LR44 button cell batteries (use our SB-2516) -Dimensions: 42(W) x 62(H) x 16(D)mm -Weighs approx. 2 grams