Intercoms & PA – GSC3516 Product Description GSC3516 Multicast Talk-Back Speaker Full-duplex speakerphone with HD acoustic chamber, advanced acoustic echo cancellation 3 directional mics, 1 omnidirectional mic Integrated Wi-Fi and Bluetooth ® One 10/100Mbps network port with PoE/ PoE+ 2-pin multi-purpose input See also different: GXP Series IP Phones – GXP1620/GXP1625 Unified Communications – GRP2636 Unified Communications – GRP2603(P) Unified Communications – GRP2602(P/W/G)