Feature:1. Self Power: The white smart doorbell uses its own power generator and does not require batteries or an external power source.2. Stable Performance: Wireless doorbell can be connected to one pager and one receiver at the same time, ensuring that call signals can be received at multiple locations.3. Elderly Pager: Smart doorbell is convenient for the elderly or people who need help to seek help through one touch calling system.4. White Appearance: Simple white design, adapting to different home styles. Meet the U.S. home appliance standard, transmitter receiver bell can be directly plugged into the power socket to use.5. Easy Installation: Wireless doorbell kit is designed to be easy to install, so you can easily and quickly install it, saving time and money on installation costs.Specification:Item Type: Wireless Doorbell Material: ABSTransmitter: Battery Type: Lithium battery, Battery Capacity: 150mAh Shipped with built in batteryReceiver: Operating Current: 60mA, Static Current: 10mAPower: 2WMusic: 52 musicOperating Frequency: 433MHzAdjustable Volume: 20 to 80dB(4 speed cycle adjustment).Package List:1 x Transmitter1 x Receiver1 x Base1 x Double Sided Adhesive Tape2 x Screws2 x Expansion Studs1 x Multi Language Instruction Manual