A high-performance sealant designed especially for HVAC applications. It provides a long-lasting weather-resistant seal with great adhesion, flexibility and durability. It adheres to most common building materials and remains flexible from -40 to 475 deg F. Meets Fed Spec. TTS001543A, ASTM C920, FDA Reg. No. 21 CFR 177.2600 and NSF/ANSI Standard 51. Safe for incidental food contact and is for interior/exterior use.Extreme temperature formula