Wireless Intercom Phone BigWireless Communication: The system uses radio frequency (around 433MHz or 462MHz, depending on the model) for clear, secure digital communication. Range: It offers a communication distance of up to 1000 meters in open areas and approximately 40 100 meters with internal wall obstructions. Scalability: A single host unit can typically connect to many extension units (up to 100 or even 999 extensions depending on the manufacturer). Power: The units are