1) Heat characters: the temperature of thermocouple on flame is 600-700 and the heat potential should≥15mv

2) Cool characters: the temperature of thermocouple on flame is 600-700. The heat potential should be≤1.5mv when 1.5min if it heated for 5min and then cut off the power.

3) Work temperature: the top temperature is lower than 700 and the other parts higher than 125

4) Remarks: The product contact the contain sulfide or the corrosive material .its performance will fall .

5) Inner resistance: accord to its type and length and the tolerance is in ±10% as is requested.

6) Length according to request of customers

7) Forehead terminal according to request of customers.