Insulator type thermocouple elements have been used since the turn of the century. When used inside a thermowell or protecting tube they can provide reliable, low cost service in many applications. Extra care should be taken to protect insulator type elements from chemical contamination which can cause erroneous readings to develop. Insulator type thermocouples can be shortened in the field in a matter of moments by simply removing one or more insulators and cutting the conductors to the desired length.