CITIZEN MG0000 - Manual (Page 141)

3.2.2. Hour Format
Select [12 Hour Format] when you want to display the watch current time using a 12 hour format.
Select [24 Hour Format] when you want to display the watch current time using a 24 hour format.
3.2.3. Timer
Preset time-min
Specify the time at which the timer is to be set.
Times from 1 to 99 minutes can be set.
Alarm Sound
You can select the alarm sound by clicking on the button with the mouse.
12