NETBELL-K Web-Based Signal Bell Self-contained All-in-One School/Factory Break Bell System with Up to 500 Event Schedules 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, flexible and accurate control of when the bells ring (HH:MM:SS, SUNDAY-SATURDAY) Features a high quality 6-inch high output bell (86db) and a completely wired web controller installed within a nema-rated box