Product Name: SudokuModel Number: RHD-102Place of Origin: ChinaFeatures: 1) Three modes: easy / medium / hard 2) Every mode can automatically generate many puzzles 3) With memory function, can record rate of the game and the highest grades 4) LED back light function, intelligentize control, with manual or automatic option 5) Sleep function: automatic enter into sleep state when the work time up to 10 minutes, when you turn on the game next time it would continue 6) Automatic proof answer, press submit to examine the answer when finished game along with displaying right or wrong, and corresponding sound as well 7) Cursor design: in order to look over, the digit has fixed cursor, twinkling cursor displays in currently position to move convenience 8) Big screen LCD display, suitable for day and night (need to turn on the LED backlight) 9) Key sound hint, different key use different sound hint function and prevent mistake from operation