Linortek Netbell-4 TCP/IP Ethernet 4 Zone Bell Ringer Web-Based Bell Controller for Alarm Signal Bell/Horn/Buzzer and Other Timed Equipment POE Built-in web server with up to 500 web-based bell timers / event scheduling software, each schedule can set different duration for different event Import/export bell schedules from existing data in text format Program and web page interface are upgradable over the internet, no additional software or designated computer required Built-in real time clock synchronizing with NTP server every 10 minutes (user changeable), flexible and accurate control of when the bells ring (HH:MM:SS, SUNDAY-SATURDAY) 4 relay outputs (1-Form-A relays 48 Volt Max 1A) for bell control, two digital inputs for adding external switch to ring bell manually