Convenient UseIdeal for use as an alarm for those who need help quickly, such as the elderly, children, disabled, pregnant women or sick patients, just press the button to call for timely and considerate care, it can also be used as a doorbell. Widely used at home, hospital, community, restaurant, office, etc. Easy to UsePlug the receiver into the power outlet wherever you need remember, the waterproof transmitter can be worn as a pendant or placed at the bedside. The 90~250V mains-powered receiver works with a low power consumption transmitter that enjoys long standby time. 52 Alert Options 80m Range52 alert sounds to choose from, with flashing LED alert. Volume adjustable in 4 levels, max 110db ideal for the elderly. No switch is designed to avoid missing the important emergency alarm. Up to 80 meters range in open area (walls and other objects will reduce the range), no interference with other devices. Call modePress the SOS button once ( 1-2 seconds), the receiver will alarm once. If you need continuous alarm, please press the SOS button repeatedly. Low battery indication1, if no operation but the transmitter LED indicator light keeps flashing , means the battery is low, please replace the batteries; 2, the association between the transmitter and the receiver may be lost after replacing the battery, pair them manually to fix them; 3, use a flat screwdriver (not included) to pry the side of the transmitter to replace the battery. Specifications: Color: white Tramitter Powerful: 90-250V Transmitter power: 1 CR2032 battery (included) Range: 80m Pairing Instructions: 1. Press and hold the volume button on the receiver until the LED lights up; 2. Press the call button once to establish a link with the receiver. 3. The blue light will flash to confirm successful pairing; 4. The receiver will automatically exit pairing mode; 5. The system is ready to use. Repeat the process if the call button and receiver lose connection. Package Included: 2 x Transmitter(random color of lanyard) 1 x Receiver Warm Tips: There is no power switch designed to avoid forgetting to turn on because it may miss an emergency call.