The Eartec UL5S is a full duplex professional intercom for five people who need to communicate and work with their hands. This compact system features five UltraLITE wireless headsets, one "Master" that sets digital sequencing, and four "Remote" headsets. UltraLITE uses digital enhanced wireless technology (DECT) to provide professional, simultaneous wireless communication within a quarter-mile range. The UltraLITE series is a breakthrough because all electronics, including the battery, are integrated within the earcups of the headphones, eliminating frayed cables and spokes. The system does not require a base station and the headsets are field programmable, meaning the system can be expanded at any time. No FCC license required. - UltraLITE Single Earbuds: UltraLITE earbuds outshine all other full-duplex wireless systems for performance and comfort because the transceiver is built right inside the earbud. This self-contained, all-in-one design eliminates headphone cables and even belt-mounted radios. They provide simultaneous conversation, two-way voice communication for users who need to work with their hands, but also require a free ear to hear what is happening around them. The microphone boom arm rotates 270 degrees. so that the headset can be used on the left or right. The microphone is muted when in the up position. - Field-replaceable lithium battery: Each UltraLITE wireless headset comes complete with a rechargeable lithium