Apollo Series 65 Heat Detector 55000-122APO A1R Class A1R Set temp 57°CThe Series 65 Heat Detector monitors temperature by using a dual thermistor network which provides a voltage output proportional to the external air temperature. There are 12 heat detectors in the Series 65 range designed to suit a wide variety of operating conditions. Can be used for applications where smoke detectors are unsuitable Ideal environments that are dirty or smoky under normal conditions Wide operating voltage Flashing LED and magnet