To ensure you can see everything in dark environments, the watch display is illuminated by a LED at the push of a button. An LED blinks when an alarm, countdown time, or hourly signal is reached. Stopwatch function - 1/100 sec - 24 hrs: For athletes and anyone who wants precision, elapsed time, split time, and final time are measured with an accuracy of hundredths of a second. The watch can measure up to 24 hours. The countdown timer helps remind you of special or recurring events by emitting an acoustic signal at the set time - afterwards, it automatically counts back from the preset time. The time can be set in seconds and up to 24 hours in advance. This function is particularly useful for daily medication intake or interval training. No matter how the appointments are spaced, this watch has the right alarm. A total of four variants are possible: 1. Daily alarm, sounds at the same time every day, 2. Date alarm, to remember birthdays, 3. Monthly alarm, sounds on the same day at the same time each month, 4. Alarm for every day of a specific month.