3.45" backlit display3 line appearances supporting up to 12 call appearances or features4 softkeys, 4 navigation buttonsBuilt-in full duplex speakerphoneDual message waiting indicatorsVolume, menu, message, speaker, headset, contacts, and call log buttonsBuilt-in two port Ethernet switch for connection to LAN and collocated PCSupports wideband audio codecBuilt-in headset interface9620L vs. 9620 - The Avaya 9620L is a low power consumption model (Class 1 PoE device). It has the same functionality as the original 9620 but does not have a USB port or adapter interface for adjuncts. It does not support SIP protocol.CompatibilityIP Office R6.0 or higher only on IP500 and IP500 V2 control unitsAvaya Communication Manager R3.1 to 5.1 - H.323 version supported; SIP not supportedPowered via 802.3af PoE (Class 1) or local 1151 power supply (sold separately; see drop down option above)