The display has 3 different light levels, so you can choose the brightness that suits you.The wake-up function works even if you turn off the screen.
 
The alarm clock can be powered by a USB cable or batteries.
 
When running on battery power, the screen will only illuminate briefly if you press any button.
 
With a USB cable, the screen stays illuminated the entire time.
 
You can select the time format – 12 or 24-hour display.Batteries are sold separately; 3 pcs LR03 AAA 1.5V required.
e recommend using alkaline batteries in the clock.1.5 metre USB cable is included.