When repairing a furnace, and the pilot assembly is removed, proper care muse be taken to ensure that when the thermocouple and pilot are reinstalled, the thermocouple must not come in contact with the ____ or it will be destroyed.

When repairing a furnace, and the pilot assembly is removed, proper care muse be taken to ensure that when the thermocouple and pilot are reinstalled, the thermocouple must not come in contact with the ____ or it will be destroyed.