The Cisco CP-8831-MIC-WRLS= Wireless DECT Microphone Kit is an essential accessory designed to expand the audio coverage of the Cisco Unified IP Conference Phone 8831 conference phone. The kit includes a pair of wireless microphones using DECT (Digital Enhanced Cordless Telecommunications) technology. This technology ensures excellent and interference-free audio quality, with an extended operating range, typically up to 300 feet (about 91 meters) in the open field. The microphones allow participants to sit away from central unit 8831 to be heard clearly, improving the conference experience in large meeting rooms or with unusual tables. Main technical specifications Model: Wireless DECT Microphone Kit for Cisco CP-8831. Product code (PN): CP-8831-MIC-WRLS=. Type: Accessories for Telephone Conference. Compatible device: Cisco Unified IP Conference Phone 8831. Kit content: Pair of Wireless microphones (2 units). Wireless Technology: DECT (Digital Enhanced Cordless Telecommunications). Operating range: Up to 90 meters (about 300 feet) in line of view. Function: Extend the audio coverage area of the conference. Advantages: Greater positioning freedom, crystalline audio, expansion for large rooms. Power supply: Built-in rechargeable battery.