Robust interoperability - Compatible with a broad array of sip call platforms to maximize voice quality and feature Availability, while simplifying management and Administration Flexible configuration options - Provides multi-unit connectivity and expansion microphones, and integrates with Polycom HDX, to meet the needs of many different types of rooms Polycom HD voice - software and hardware technology brings lifelike Audio clarity, making your conference calls more efficient and productive - built-in power over Ethernet (PoE). an optional a/C power kit also available Polycom acoustic clarity Technology - delivers the best conference phone experience, without compromises; Microphone pick up range - 6 m/20 ft Built-in 2. 5mm applications port, which enables you to connect the conference phone to a mobile phone for productive calls even where no network connection is available (or to a computer for calls using PC-based soft phone clients)