Where Concept 4000 hardware is installed in locations and environments where a very high level of electrical transient activity might be anticipated, the addition of Inner Range Advanced Surge Protection Devices adds a further layer of transient protection. There are three unique Inner Range Advanced Surge Protection Devices with each device purpose built to provide additional protection inline with the most vulnerable components of the system circuitry - the phone line, the power supply and the Concept RS-485 LAN.