The PR 1776 S is a low gravity sprayable aircraft integrated fuel tank sealant. The PR 1776 class S was developed specifically for use in the temperature range of -55 ° C to + 95 ° C to 180 ° C and is exceptionally resistant to aviation fuels (aviation gasoline or jet fuel) and petroleum-based lubricants.

The PR 1776 class S is a two part polysulfide liquid polymer. The mixed compound is in a liquid consistency that can be spray applied, when applied around fasteners it does not drip or flow from vertical or top surfaces. The sealant has excellent adhesion to aluminum, titanium, stainless steel and other metals.