When the timer exceeds 24 hours, the stopwatch will advance one digit to count the days. As shown in the figure below, the time 3:01:21:06 represents the time unit of day, hour, minute, and second, that is, the time represents a total of 3 days, 1 hour, 21 minutes, and 6 seconds.
The time has not exceeded one hour, and the stopwatch displays three-time units. That is, the time units represented by the time 00:18.83 shown in the figure below are minutes, seconds, and milliseconds respectively, that is, the time represents the accumulated time of 18 seconds and 83 milliseconds.