Product information:Color whiteVolume: 60 (dB)Working voltage: 4.5 (V)Size: Pager: 4.2*8.5*1.5cm Receiver: 4.8*12.7*2.7cmPacking list: 1 * pager, 1 * receiver Convenient and ReliableIdeal for use as an alarm device for those who need help quickly, such as the elderly, children, the disabled, pregnant women or the sick. Just press the call button to get timely and considerate care without shouting. It can also be used as a doorbell. Long RangeUp to 180 meters range in open area (walls and other objects reduce range). By using 16-bit encoding to eliminate interference from other devices, you can work from virtually anywhere in your home. More alarm options 32 sounds (23 melody sounds and 9 alarm sounds) to choose from. No power switch is provided to avoid forgetting to turn on. This can lead to an important emergency call. (If you don't use the device for a long time, take out the batteries to protect the battery life). Convenient PlacementThe waterproof transmitter can be worn as a pendant or bedside. The receiver can be wall mounted, free standing on a desk or carried in the caregiver's pocket. Low battery indicator 1, No operation, but the device indicator flashes or makes an unusual sound. Please replace the battery. 2, The connection between transmitter and receiver may lose contact after battery replacement. The items are not defective. They just need to be paired manually to fix the problem. Receiver is powered by 3 x AAA batteries (not included); Transmitter with 1 x button cell (included).