3M EBI-4 Fire Barrier Electrical Box Inserts

3M™ Fire Barrier Electrical Box Inserts are a flexible, one-piece fire-rated intumescent insert used to protect electrical boxes by adhering to the inside the box. When exposed to fire, the insert expands to fill up the box preventing the spread of fire and limiting temperature rise.3M™ Fire Barrier Electrical Box Insert (EBI) is designed to help prevent the spread of fire in 1 and 2 hour rated gypsum wall assemblies when penetrated with metallic electrical boxes in the event of a fire. When exposed to a heat source, the material expands to seal the airspace inside the box and forms a char to deter the spread of fire.