- NEC 4ATRU 4 Port Analog Trunk PCB - Supports 4 analog loop start CO trunks - Mode switch for taking the PCB out of service - Status LED indicating proper PCB operation - Port activity LED that indicates traffic on the PCB - 2 Power failure cut through circuits - Upon failure of commercial AC power PCB automatically cuts through 2 trunk circuits to 2 power failure telephones - Built-in caller ID
