Battery Powered ClockThis digital clock is only powered by 2 AA alkaline batteries (not included), You don't need to press any button to see the time at night. 12 or 24 hour time formats. Bright LED Time Display24 hours bright 1.2" large LED hour digits can let you read clearly your time remotely or even in the dark and without any operation. (Note: It cannot be placed in a very bright place or the display will become blurry.) Daily Alarm Clock and High AccuracyThe alarm clock works for 90 seconds to wake you up permanently. The alarm tone gets louder every 30 seconds. The time accuracy of this watch is within +/- 30 seconds per month. Desk And Wall ClockPerfect for children, teens, adults, seniors and the elderly, simple bedside table gift alarm clock. Portable alarm clocks come with a warranty