Three-way wireless audio doorphone

Wireless audio doorphone allows you to talk to your visitors before opening the door,No wires required between the door bell and the phone making this system very easy to install.Good for security and helpful for the elderly or less mobile .Works up to 150 metres .Waterproof outdoor unit (IP44 rated) •2.4GHz Wireless Digital transmission of audio signal excludes external interference and promises clear voice.•Indoor unit with door release function.•Anti-oxidation, durable aluminum outdoor .Approriate for three family.