【Built-in Battery + USB Charging】We've included a USB charging cable. With a built-in 500mAh rechargeable battery , this alarm clock retains your settings even in the event of a power outage. Perfect for travel or power outages. 【Luminous and light function】1,Luminous function Instructions: The dial and hands glow a night after the insertion of a normal interior light for a whole day or sunlight. With constantly illuminated dial, you can see the time at night. However, its light will gradually dim. If you want it to shine again, please expose it to sunlight or a light source for a period of time to activate its brightness. 2,light function Instructions：A LED light bulb built into the clock , you can also press the button to activate night vision.But when you take your finger off the button, the LED light will turn off; it's not always on. 【High-quality environmental protection material】The non-ticking alarm clock case is made of metal material, 3 meters anti-drop, the dial is made of plastic material, non-toxic and tasteless, beautiful in appearance. 【Exquisite and compact alarm clock】This alarm clock is exquisitely crafted, compact . It can be placed on the bedside table or on the children's table to remember the time, it is a good helper for children.edside table or on the children's table to remember the time, it is a good helper for children. 【A must for bedside table】This bedside clock is very easy to set the time and alarm for everyone, a perfect gift for your family and friends. This bedroom clock protects you from radiation damage, lets you stay away from your phone while sleeping, no need to set an alarm on the phone.