Can Be Paired With Self-powered Wireless Doorbell, Intelligent Electronic Remote Control Doorbell Features: 1.32 Songs Home Welcome Door Chimes 2.150M Long Wireless Control Distance 3.Waterproof Door Bell 4.Four leverls of volume 5.Self-Power,No battery required Strong Signal:150M Long Wireless Distance It can penetrate 3-4 walls and wireless range up to 150 meters in open area,great for large house including willas, apartment,offices,shops,warehouses.etc. Waterproof Door Bell:IP68 Waterproof level Rainy days can also be used,saed and durable The doorbell can be muted when sleeping Not only a doorbell but also a pager When the elderly,babies,and pregnant women sleeping alone have needs,press the transmitter and the bell will ring. Smart learning mode User-friendly design Multi-type plug interface, EU UK US Plug ,there is always one suitable for you