1.PT100 Type thermocouple ternperature sensor which is ususally work with tempeter meter.2.With 3 fork design thermocouple, temperature sensor for accurate measurement.3.Silver tone flexible spring built in, protect the wire and probe.4.A thermocouple is a device consisting of two different conductors (usually metal alloys) that produce a voltage 5.proportional to a temperature difference between either end of the pair of conductors