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. 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. 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