The SPD50K Series offers easily monitored protection from surges. It can be installed via 3/4" NPT, DIN-Rail or bracket mount anywhere in any electrical distribution system; line-side or load-side of main disconnect. The LED is visible from multiple sides and angles to allow for better viewing of the status from any of the tri-mount options. The visual diagnostic system that is featured in the SPD50K is easy to see and easy to diagnose. When the Green LED is visible, the protective device is okay and working correctly. When the Green LED is extinguished, the equipment should be replaced as well as an audible alarm.