Product description Features: DC 3V power supply A total of 8 timing rules For each rule, the basic time and auxiliary parameters can be set separately according to the dial switch at the bottom (the 2 parties can set different basic time), and the alarm can be set or canceled. The alarm lasts for 10 seconds at the end of the game (alarm does not exist if it is in the silent mode). At the end of the game or when the game is paused, you can press and hold the reset button for 3 seconds to quickly reset the rules. Time can be set. Time and times can be calculated individually or in multiple combinations) 1. Basic time: 3 5 10 20 40 80 (minutes) 2. Increment time per step: 12 3 5 10 20 (seconds) 3. Time limit for each step: 3510204080 (seconds) 4. Countdown times: 12351020 (times) 5. Countdown time: 125102040 (seconds) Specifications: Name: Multifunctional Chess Clock Switch: power switch/alarm switch Size: as shown in the pictures Packing List: 1 x Chess Clock