PR-1776 C级是一个低密度，高温度飞机整体燃料密封。工作温度范围从-65°F（-54℃）至250°F（121℃），间歇性偏移高达360°F（182℃）。

PR-1776 Class C is a low density, high temperature aircraft integral fuel tank sealant. It has a service temperature range from -65°F (-54°C) to 250°F (121°C), with intermittent excursions up to 360°F (182°C).

这种材料是专为圆角密封油箱和其他飞机机身密封应用。尽可能多节约20％重量，每单位体积，超过传统密封较

长期接触航空喷气燃料和天然气后，固化的密封剂仍保持弹性。

会抵制有限接触二磷酸托架液压液。

PR-1776M C类是由两部分组成，二氧化锰固化PERMAPOL®P-5改性聚硫。未固化的材料是一种低弧垂，触变性膏状适合配合挤压枪或抹刀使用。

室温下固化，形成有弹性的密封剂，对常见的飞机基板具有优异的粘附性。

This material is designed for brush sealing of fuel tanks and other aircraft fuselage sealing applications. It offers as much as a 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.

PR-1776 Class C is a two-part, manganese dioxide cured Permapol® P-5 modified polysulfide. The uncured material is a roller grade liquid suitable for application by brush, extrusion gun or spatula. It cures at room temperature to form a resilient sealant having excellent adhesion to common aircraft substrates.