Linortek Netbell-8 TCP/IP Ethernet 8 Zone Bell Ringer Web-based Controller for 12V/24V 5A Alarm Signal Horn/Buzzer & Other Timed Equipment Built-in web server with up to 500 web-based bell timer/event scheduling software for relay control 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) Eight low voltage relay outputs (1 form c 24vac/dc 5a) for bell control, power supply and internet cable included Compact and self-contained, supplied with the hardware and software you need to control your existing bell timer devices