- This is a unique wireless doorbell; the key difference from other plug-in doorbells is the push-button self-generating power technology, requiring no battery or wiringpower is generated automatically when the button is pressed. - Operates up to approximately 200 meters in open areas; the push-button transmitter is IP44 rated for water resistance, suitable for outdoor use. - Features 48 selectable melodies and 6 adjustable volume levels. - Includes an LED indicator; supports adding extra transmitters or receivers to meet your needs, ensuring the chime can be heard throughout the home to avoid missing visitors. - Easy to install with no wires or drilling required; simply mount the transmitter outdoors and plug the receiver indoors for convenient home security. Specification: Material: ABS Plastic Transmitter: Approx. 75x42x22mm / 2.95x1.65x0.87 inch Receiver: Approx. 90x60x30mm / 3.54x2.36x1.18 inch Working Distance: 200m Voltage: AC 110V220V Plug Type: US Package Includes: 1 Set Wireless Doorbell Note: 1. Due to manual measurement, slight variations in color and size may occur. 2. Keep both transmitter and receiver in sheltered locations to avoid exposure to water and direct sunlight. 3. Clean the transmitter regularly with a damp cloth to prevent dirt buildup that may obstruct function. 4. Press the button firmly to ensure sufficient power generation.