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. Five year warranty.

• Large, bright .9" tall green digital display (LED) with adjustable angle for easy reading!
• Adjustable loud buzzer up to 98 decibels
• Adjustable volume and tone controls lets you pick the perfect volume and tone to best alert you
• One switch lets you choose any or all of the lamp, vibrator, or buzzer signals
• Has ON/OFF switch for using lamp as a reading light
• Snooze
• Vibrator control allows steady or pulsing vibrations for best alerting
• Built-in deluxe remote receiver works with any Sonic Alert transmitter
• Test button to allow for easy setting of controls
• Auto-Dimmer automatically reduces display level when the room gets darker
• Dimensions: approximately 4-3/4" W x 5" D x 3-3/4" H
• Modified L-shape vibrator jack improves performance of vibrator.

Read owners manual here