This is a reliable J-type thermocouple. The beaded J-type sensor is at the tip of a 3ft long wire probe, which has a medium temperature fiberglass insulation, good up to 752 degree Fahrenheit °F or 400 degree Celsius °C. It has a miniature type thermocouple connector (2 flat blades made from J-type thermocouple metal iron and constantan) that will work with digital J-type thermometers of many manufacturers. This probe can used to measure air or gas temperatures, non corrosive liquids and it can be attached to pipes or embedded into objects you want to measure. This J-type thermocouple probe also measures down to about -292 F (make sure the electronic thermometer is capable of measuring that low). It is frequently used in the laboratory to measure dry ice (solid carbon dioxide) and very cold cooling liquids in cryogenics. J-type thermocouples are also used in the wood industry for measuring wood drying kilns. The thermocouple connector can easily be opened and you can shorten the beaded wire J-type thermocouple if desired.