Teflong or PTFE gaskets the best option for highly corrosive environments. PTFE is a versatile material with a broad range of resistivity to chemicals and
temperatures (-100°F - 450°F), and virtually no extractables. PTFE is a
plastic, however, and is subject to creep and cold flow. PTFE gaskets
should be used almost exclusively with high pressure clamps and are not
recommended where large temperature variations occur
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