The Eartec UL3S UltraLITE is a 3-Person Wireless Intercom system for use in mobile video production, field production, live sports, theater sets & sounds stages. The lightweight (4 oz) yet solid construction of system headsets allows for hours of comfortable use and with a 6 hour battery life there's no need to worry about getting cut off during that critical take or cue! Systems cover a huge ¼-mile range. Headsets feature a convenient “mic-mute” by simply swiveling the boom 270° upward. Kits include a HUB mini-base station, master headset, remote headset, battery charger and carry case. UltraLITE Headsets Features 1 UltraLITE Single Muff Master and 2 UltraLITE Single Muff Remote headset. UltraLITE headsets are full duplex wireless headsets that provide hands-free, two-way voice communications. At the heart of these systems, the "Master" headset relays the digital signals generated by the "Remote" headset units. This is a 3-Person system - you can add up to 6 remote users to your system with the purchase of additional headsets and the addition of a EAR-HUB if more than 4 users is required. The resulting open line talking pattern allows users to talk simultaneously without pushing buttons. All UltraLITE headsets are powered by a Lithium Polymer battery that will operate 6 hours when fully charged. The Eartec HUB is required when using more than 4 UltraLite remote headsets. Up to 7 systems in total can be used when the HUB is added. Please Note Once you have added the HUB and one of the 3 wired headsets to your UltraLite system, the HUB becomes the master, all other communication can only be transmitted by using "remotes".