On Tuesday, November 20, 2012 8:35:52 AM UTC-8, Spehro Pefhany wrote:
Anything better than PTFE/Teflon for high temperatures?

Auto stores stock a variety of (usually Permatex brand) sealants
in RTV silicone, including a variety of removable sealants.
If you ever replace/repair threaded fittings, the nonremovable
ones are not recommended.