Features3 lines, 6 SIP accounts, up to 3 call appearances Supported by GDMS, which provides a central interface for configuring, deploying, managing and monitoring Grandstream devices EHS (Electronic Hook Switch) support for Plantronics, Jabra and Sennheiser -Headsets Full duplex speakerphone with HD audio to maximize audio quality and clarity Equipped with noise shield technology to minimize background noise Two switched autosensing 10/100/1000 Mbps Gigabit Ethernet ports with integrated PoE (GRP2604P only) Supports 5-way audio conferencing for easy conference calls Enterprise-level protection with secure boot, dual firmware images and encrypted data storage Interchangeable faceplate for easy logo customization