Features: The energy is converted into electric energy.No Battery Required, Energy saving and environmental protection. Button is Waterproof IP44. Don't worry about extended use in heavy rain. Signal is stronger, enhanced wall penetration and propagation distance. Advanced A12 microprocessor, more anti-interference.The neighbor's doorbell will not interfere with our doorbell. Free Matching: Learning Code Technology,Buttons and receivers can be paired freely. No Fever,Safer: Upgraded IC circuit.It will not heat up when plugged in for a long time. Better security. Designed to last up to 26 years LED Flashing: The mute setting can avoid disturbing the baby's sleep. There is a LED flashing light reminder when guests ring the doorbell. Easy Installation: No wiring required, no tools required you don't necessarily have to make holes or damage anything. 1. Plug the receiver into the socket. 2. Double-sided tape or screws on the back of the button. 3. Stick the button to the outside wall. Specification: Receiving distance: 150M (in open area). Waterproof: IP44. Ringtones: 51 pcs. Volume:4-steps(Can mute). Button power supply: Self powered. Receiver power supply: AC110V-250V. Plug Type: EU / US / UK / AU. Working frequency: 433 MHz. Package included: 1 x Receiver. 1 x Button. 1 x English manual. 1 x Accessories