Specifications:

Features:

1) Between hands-free intercom extension and master can call and talk;
2) Can output for button of exigency alarm;
3) Hands-free and easy used, with ultra-thin intercom function

4) there are two buttons, one little round button, one red button with long-line, so patient can lay on the bed to press the button conveniently.
5) Connected to the master by 4-wire bus cable

System Diagram: