J-Type is suitable to use between temperature -210°C and +350°C. It has great EMF, and ranks 2nd amongst all thermocouple types (only E-Type has better EMF). J-Type's disadvantage is that it uses Fe as its positive conductor, which can get rusty in high humidity environment. Passed UL VW-1 Vertical fire test and multiple IEC tests, proven to be low smoke density, halogen free, and flame retardant.