This chess clock is suitable for most kinds of chess games. It has 42 kinds of timing rules. It is easy to operate and can be silent, provides a nice timing tool for games.    Features:  With countdown function, can carry out multi section countdown, positive timing function and each step delay function.  It can add seconds, limit times and read seconds.  Different timing parameters can be set on the left and right sides. During the competition, the timing parameters of both sides can be modified.  Can display the number of chess steps, can be silent, does not affect players playing chess.  Turn off the machine and turn it on again to keep the parameters of the game before turning it off.  Big seesaw button, nice handle, quick reaction, easy to control.  It has 42 preset rules, multi-function and wide ranges of application.    Specifications:  Material: plastics + metal  Battery: 2 * AA: 1.5V, 800mAh (Delivered without batteries)  Item size: 161 * 100 * 62mm / 6.3 * 3.9 * 2.4in  Item weight: 245g / 8.6ounce  Package size: 150 * 100 * 50mm / 5.9 * 3.9 * 2.0in  Package weight: 400g / 0.9lb Packing List:  1 * Chess Clock        YS-902  Specifications: Material: ABS Color: Black  Battery: 2 * AAA battery (Not included) Screen size: 103 * 23mm / 4.06 * 0.91in Item size: 140 * 88 * 45mm / 5.51 * 3.46 * 1.77in Item weight: 105g / 3.70ounce Package size: 150 * 100 * 50mm / 5.91 * 3.94 * 1.97in Package weight: 157g / 5.54ounce Packing List: 1 * Chess Clock