For chess matches: no batteries needed and powered by clockwork. Lightweight and easy to use, it's the timing tool used in most chess matches in European and American countries. High precision: the daily error is no more than 1 second. It is suitable for timing clocks in various chess sets. Mechanical structure: Adopts a mechanical structure with a timing start button, making the timing operation intuitive, convenient, and accurate. Material: wood and plastic, durable and not easy to break. Wood color design, looks exquisite. Maintenance: The chess clock should avoid contact with corrosive objects, avoid exposure to sun, rain, drips, and close to strong magnetic fields. 1. For chess matches: no batteries needed and powered by clockwork. Lightweight and easy to use, similar to quartz clock working mode. It is the timing tool used in most chess matches in European and American countries. 2. Mechanical structure: Adopts a mechanical structure with a timing start button, making the timing operation intuitive, convenient, and accurate. Usage: 1) Timing button operation method: Press the left button to stop the timing of the left clock and start timing the right clock. Conversely, press the right button, right to stop timing, left start timing, both sides of the button pressed simultaneously under half (i.e., both sides of the button in the same position horizontally), two clocks are in stop state. 2) Zero adjustment of the second hand: By alternately using the buttons on both sides, the two clock and second hands can be adjusted to the 12 o'clock position (zero) in turn, and the hour hand can be moved to the 12 o'clock position according to the direction of the needle hole on the back of the clock. In the game clock, the minute hand takes zero dom the minute hand to push the "little red flag" judgment mark to the right to reach the 12 o'clock position, and the scale pointed by the minute hand when the "little red flag" falls freely is zero. Specification: Material: wood + plastic Color: Wood color Size: approx. 15.5x5.5x9.5 cm / 6.10*2.17*3.74 inches (Length*Width*Height) Package included: 1 x Chess Clock Note: all data are manual measurements, please allow 1-3 cm error, due to the light and display difference, there will be some color difference, subject to the physical object received.