Eartec UltraLITE are breakthrough full duplex wireless headsets that provide hands-free, two-way voice communications. At the heart of these systems is a specialty "Master" headset that relays the digital signals generated to the "Remote" unit. The resulting open line talking pattern allows umpires to talk simultaneously without pushing buttons. Easy access up and down volume buttons. Auto-mute by raising boom mic into vertical position. Use earcup over either left or right ear. These DECT Systems (digital enhanced cordless telecommunications) feature miniaturized wireless circuitry and antenna built into the earcup. This provides a streamlined, all inclusive headset. No beltpack is required. 1-year warranty and 30-day "no questions asked" money back guarantee (buyer pays for return shipping).