PR-1782 Class C is a low density, aircraft fuel tank and general sealant. It has a service temperature range from -54°C to 121°C (-65°F to 250°F). This material is designed for fay surface sealing applications. It offers as much as twenty percent weight savings, per unit volume, over traditional sealants used for these purposes. The cured sealant maintains excellent elastomeric properties after prolonged exposure to aircraft fuels both jet fuel and aviation gas, and will resist limited contact to diphosphate ester based hydraulic fluids.