PT1000 sensor overvoltage protector in a splash-proof IP65 protective case. Protects the collector sensor against local lightning strikes and externally induced voltage spikes. A varistor protective diode protects against atmospheric overvoltages that can lead to the destruction of the collector sensor. Recommended for extra protection of the collector sensor in any type of solar thermal system. Simple installation in the sensor extension wire via spring terminals. Special order item, may take an additional few days to arrive.