Permatex Clear RTV Silicone General-purpose, clear RTV indoor/ outdoor sealant. Seals, bonds, repairs, mends and secures glass, metal, plastics, fabric, vinyl, weather stripping and vinyl tops. May be applied to horizontal or vertical surfaces. Permatex® Clear RTV Silicone Adhesive Sealant is waterproof and flexible. Temperature range -75°F to 400°F (-59°C to