Timing rules include BASIC, BONUS, DELAY, BYO-YOMI, and COUNT-UP; automatically switches to positive timing mode after countdown. User-defined time can be set up to 9:59:59; different timing parameters can be set for both sides; time can be modified during operation. Automatically saves the previously set parameters before shutdown. Step recording function allows viewing or modifying up to 999 steps. Sound and shutdown settings: enable or disable prompts, turn the chess clock on or off. Functions: BASIC: Standard timing mode in current time DELAY: Delay timing mode in current time BONUS: Bonus time added after each move BYO-YOMI: Go-style countdown timing mode Battery: 2 x AA batteries (not included) Note: Installation guide not included; professional installation is recommended. Please verify the item meets your requirements before use. Product design may vary slightly between batches; minor differences in color or appearance may occur due to production updates—this does not affect functionality. Color: Dark Blue Material: Plastic Package Contents: 1 x Chess Timer Only the items listed above are included; other accessories are not part of the package. Note: Lighting conditions and display settings may cause slight variations in color representation. Measurement tolerance: ±1–3 cm.