The majority of all surge-induced damage is caused by surges and spikes traveling along unprotected data lines. These surges originate from a wide variety of sources, including static charge buildup and lightning strikes. Left unprotected, your data lines expose network cards, A/V components, modems and other network equipment to damaging electrical transients. The ProtectNet RS-232 Surge Suppressor protects individual data lines. Inserting it in your data line and connecting it to earth ground prevents back-door surges from ruining your productivity and costing you money.