Thermocouple elements (unless other wise specified) are constructed using a metallic sheath and high purity mineral oxide insulation. This provides a rugged and bendable design that exceeds the temperature rating of non noble metal calibrations. Mineral oxide type thermocouple elements have a high insulation resistance and are suited for most process applications. Smart thermocouple elements are available in all calibrations with a variety of sheath materials and diameters, such as our high temperature furnace thermocouples.