Sudoku Game Machine Product Code: WS-152 Features: Real-time clock; Alarm function, with enjoyable musical melody built-in as the alarm sound; There are total of 5 levels of difficulties to choose from; There are 999 fixed games under with difficulty level, the fixed quiz counted up to 4995;Over ten thousands of random games were built-in for each difficulty level; Manual Game Editor function, No need to use pen and paper and the game could played easily in this product.