The TH-21 Series thermistor probes are constructed with the a glass encapsulated thermistor element which provide excellent stability and accuracy. With a maximum continuous temperature rating of -80 to 200°C (-112 to 392°F), and intermittent operation to 250°C (482°F), these thermistor sensors can be used in applications previously out of reach of epoxy coated thermistor sensors. The probes can be ordered in any length but we highly recommend a minimum immersion depth of 1.5". Short probes run the risk of error due to stem conduction effects. Ideal for laboratory , R&D, automation and automotive applications. Perfect for the HVAC, manufacturing and chemical industries.