PR-1440® Class B are aircraft integral fuel tank sealants. It has service temperature range from -65°F (-54°C) to 250°F (121°C), with this intermittent excursions up to 275° (135°C). This material is designed for brush sealing of fasteners in fuel tanks and other aircraft fuselage sealing applications. The cured sealant maintains excellent elastomeric properties after prolonged exposure to both jet fuel and aviation gas.

PR-1440® Class B are two-part, manganese dioxide cured polysulfide compounds. The uncured material is suitable for application by brush in thickness up to 25 mils. It cures at room temperature to form a resilient sealant having excellent adhesion to common aircraft substrates.