Gasket Sealant, Slow Dry, Non-Hardening, High Temperature -65 to 600°F intermittent, 7 oz. tube, boxed. PERMATEX (1372), Features: Slow setting, non-hardening, high temperature sealant. Especially recommended for heavy-duty applications. Temperatures range from -65˚F to 600˚F (-54˚C to 315˚C) intermittent. Resists common shop fluids. Suggested applications: Coating and sealing exhaust gaskets, flanges and connections, and other heavy duty applications.