P/S 890 Class A is an aircraft integral fuel tank sealant.
P/S 870 Class B Corrosion Inhibitive Sealant
P/S 870 Class B is a corrosion-inhibitive sealant that acts as an effective barrier against the common causes of corrosion on aluminum alloys or between dissimilar metals.
PR-1776M Class B Low Weight Fuel Tank Sealant
PR-1776M Class B is a low density, high temperature aircraft integral fuel tank sealant designed for fillet sealing of fuel tanks and other aircraft fuselage sealing applications.