Wire pair protection, in-line installation, screw terminals. In-line impedance 10 ohms. For signal voltages 5 to 170V peak (AC and DC). Bipolar operation, instantaneous and automatic. Line terminals carry the surges, equipment terminals are protected. Mounting legs connected to ground. Surge current rating 15,000 amperes for 8/20 µs and 750 amperes on 10/1000 µs wave.