Fireman Intercom Controler Up to 40 Phone Extensions

RATED OPERATING VOLTAGE DC24V, 3U STANDARD PANEL CABINET TYPE; LCD DISPLAY FUNCTION; CAN CARRY 8/16/24/32/40 EXTENSIONS; DUAL FULL-TIME CALLING, UP TO 5 EXTENSIONS CAN BE CALLED/TALKED AT THE SAME TIME; REAL-TIME SHORT CIRCUIT AND OPEN CIRCUIT FAULT ALARM; AUTOMATIC RECORDING FUNCTION; MAXIMUM TRANSMISSION DISTANCE UP TO 1500M, ETC.