Optima HD IP Conference Optima HD voice, Full duplex technology 20-feet and 360 degree voice pickup Two wireless microphones (optional) Built in 3-microphone array Android 5.1 OS 5-inch multi-touch screen with 1280*720 resolution Power over Ethernet 5-way voice conferencing Built-in Wi-Fi\Bluetooth Connect to PC via micro USB Support call recording without PSU 1 x Wireless Mics