HANAST HN-5508 A/B Low Outgassing Black Epoxy Potting Compound for Hydrogen Fuel Cell, Vacuum Electronics and Power Module Encapsulation HN-5508 A/B is a two-component, room-temperature or heat-curable epoxy potting compound engineered for vacuum electronics, new-energy power modules and other high-reliability applications. Mixed at a 5:1 ratio by weight, it flows with low viscosity and a long pot life, penetrates narrow gaps, and cures bubble-free into a smooth, glossy, high