... and diameters, such as high temperature furnace thermocouples. Mineral insulated cable for thermocouple use: Measure range: K, E, J, T, ... , TriplexSample1 MI thermocouple with J extension wireMI cable for RTD use:Conductor: Ni,CuOuter dia.: 2~8mm Sheath: SS304, SS321, SS316, SS310 ... , INC600 Class: Class A or Special Core: Simplex, Duplex, TriplexSample 2 MI RTD with connector Mineral Insulated Cable