Datavideo ITC-100 8-User Wired Intercom System With 4 Beltbacks & 4 HeadsetsOne of the innovative features of the rack mountable ITC 100 8 User Wired Intercom System with 4 Beltbacks & 4 Headsets from Datavideo is that it can use headsets ranging from low cost cell phone headsets to high quality professional units. Up to 8 users can be connected to the ITC 100 via PTT wired beltpacks. Four beltpacks, four headsets, four cables and a tally light set are all included. Cables for connecting the beltpacks may be up to 984 ft