Type-J thermocouple wire:  Made with Iron and Constantan.  Choose from three different insulation coverings including PVC, PFA, and Fiberglass.  

PVC insulation can be used up to 220ºF or 105ºC

PFA insulation can be used up to 482ºF or 250ºC

Fiberglass insulation can be used up to 752ºF or 400ºC