- Please check with your Internet Service Provider before buying, as not everybody supports this model.- Optional backup battery Sold Separately- The TM602 delivers two lines of carrier- grade Voice over IP (VoIP) and High- Speed Data access.- Benefits: DOCSIS 2.0 and PacketCableTM 1.1/1.5 compliant design High Speed Internet via 10/100 Base- T Ethernet (RJ- 45) or USB1.1 port Improved Line Card Performance over the industry leading TM502 - Greater than 20% increase in high loop current mode and 10% greater ringing voltage More Battery Options- The TM602 maintains the same modem and battery form factors, but introduces two new battery options.