[Game Clock] This clock features a mechanical structure with a timing start button. It is simple to operate: press the left button, the left timer stops timing and the right timer starts timing. Press the right button, the right timer stops timing and the left timer starts timing. Pressing both buttons halfway simultaneously stops timing on both sides.[Practical Clock] Practical PQ9905 quartz analog chess clock, suitable for Chinese chess and other chess games.[Accurate Timing] The timing is accurate with less than 1 second error, making it ideal for various chess game timing needs.[Lightweight and Durable] Sturdy plastic shell, lightweight and durable, easy to carry, suitable for novelty, entertainment, and practical use.[Molding Process] The shell uses a unique molding process, allowing the clock to be placed at a slight angle for better viewing, anti-slip, and glare-resistant screen reading.Usage Instructions:1) Timing button operation: Press the left button to stop the left clock and start the right clock. Press the right button to stop the right clock and start the left clock. Press both buttons halfway at the same time to stop both clocks.2) Second hand zero adjustment: Alternately press both buttons to adjust the second hands of each clock to the 12 o'clock position (zero). Use the adjustment hole on the back of the clock to set the hour and minute hands to 12 o'clock. When timing, align the "small red flag" indicator to the upper right 12 o'clock position. The zero position is set when the "small red flag" drops freely.Color: Black Material: Plastic Size: 18 x 6.5 x 11.5 cm Package Contents: 1 x Chess Clock Note: 1 AA battery is not included Only the above package content is included; other items are not part of the package. Note: Light reflection and differences in display screens may cause slight color variations between the image and the actual item. Measurement error allowance is +/- 1-3 cm.