Permatex hi-temp RTV silicone gasket is a single component, room temperature vulcanizing gasketing compound designed to provide reliable formed-in-place gaskets for mechanical assemblies. This material cures on exposure to moisture in the air to form a tough, flexible, silicone rubber gasket. - The product resists aging, weathering and thermal cycling without hardening, shrinking or cracking. Designed to maintain maximum performance in a continuous temperature environment of 600 °F.