SmartNode VoIP Gateway, 72 FXS on RJ11&3xRJ21-50pin, K.21 basic surge protection, 72 VoIP Calls, upgradeable to eSBC (max. 200 SIP calls), Optional SIP-TLS/SRTP, 2x Gig Ethernet, 1x USB, 1x Console, Redundant Internal UI power (100–240 VAC)