Overview: The Sonic Boom Alarm Clock is a unique clock that is guaranteed to wake up even the heaviest sleepers. When the alarm goes off, the user can select to wake up to any combination of loud pulsating audio alarm or flashing lights. Our patented adjustable volume and tone controls allows you to select the best sound combination to wake you up. The clock display also has an adjustable viewing angle with large, bright green LED numbers for easy viewing. It also has a battery back up for power outages. (9 volt battery not included) The clock has a built in receiver to pick up transmissions from other Sonic Alert signalers. This patented feature eliminates the need for separate receivers in your bedroom to alert you to your baby's crying, doorbell or telephone. There is also a test button on the unit to explore which combination of flashing lights, shaking bed or loud pulsating audio alarm will work best for you. Sleep well - live well knowing you're always connected! Specifications: 113 db extra-loud alarm (with adjustable tone ; volume control) Built-in receiver (for other Sonic Alert; signalers) Lamp connection Built-in flashing alert lights 9V battery backup, maintains time and alarm setting in the event of power failure (battery not included).