[Three alarm programs] The LED alarm clock has three alarm programs, 1-5 (Monday to Friday), 1-7 (every day), 6-7 (weekend mode). You can set workdays and weekends respectively. Wake up so you can sleep late on weekends. The default time format of the alarm clock is 24-hour format. If you need to switch to 12-hour format, please press the "TIME SET" button [USB or battery powered] The morning alarm clock is powered by a USB cable or 3 AAA batteries (not included, need to be purchased by yourself). After installing the battery, the set alarm will sound even if the power is disconnected, and the battery will remember all the "Alarm" settings. When the battery is low, the screen will display a low battery icon to remind you to replace the battery as soon as possible. After replacing the battery, the low battery icon will disappear. [2 Alarm Clocks with Snooze] The alarm clock for teens can set two alarm clocks, each alarm clock has an independent switch, which is convenient for you and