The LanMaster 30 scans all combinations of the eight wires connected to an RJ-45 outlet to identify the type of equipment connected to the far-end or warn of the detection of potentially harmful unknown signals. Identifying the outlet type eliminates guessing. In less than six seconds, the LanMaster 30 will identify a 10baseT Link, 100baseT Link, Token Ring Link, Analog Telephone Line, PBX Line, ISDN Line, warn of unidentified signals, or indicate no signals are present. The model 30 even indicates when a 10/100 Ethernet Link is configured for auto-negotiation. Requires 9-volt battery (included).