Small footprint(5.9"x3.11"x1.65") with big white LED numbers easy to read day or night, and display brightness can be easily adjusted from 0 to 100%, depending on personal preference. 12 or 24 hour time display optional. | Pick your favorite sound among the 5 alarm sound options(Beep/Buzzer/Bird Sound/Piano Music/Soft Music), and wake up to adjustable alarm volume from 30-90db. | Easy-to-use digital alarm clock. Easy snooze with a simple press of the top button and experience zero stress when setting the time or alarm. | Integrated USB port charges your compatible smartphone while you sleep. Start your fresh day with a fully-charged phone. | Outlet Powered with Battery Backup: Plug in to power the clock with the included DC adapter. The button cell battery(included) preserves time and alarm settings in case of power outage. During the backup battery, the screen will go blank and alarm will not sound.