It is a preset count timer, up to 10 hours, lightweight and portable, easy for you to carry, we will provide you with a protection bag for free to help you protect your clock from malfunction. 2 During the game, you can change the stop and then start (non-failure), and you can retain the last rule settings before shutting down. The machine must be restarted before switching countdown and countdown; 3 rewards for each step, and two delay rules for each step. Different basic parameters and auxiliary parameters can be set on the side, and the alarm will be alarmed when the game ends; 4. Made of durable ABS plastic shell, safe, environmentally friendly and durable; 5. Suitable for chess, international chess, home games and competitions;