It is DSL-compatible in both monitor and voice operation. The LCD display simplifies the reading of polarity, voltage, current, and selection frequencies, and shows the last dialed numbers as well as the numbers for speed dialing. For safe operation, overvoltage and overcurrent are displayed. Additional features include intercom mode (two-way communication), a built-in tone generator for line identification, as well as DTMF detection and measurement. With the included headset, hands-free operation is possible.