This advanced flexible intumescent acrylic latex fire stop sealant "intumesces" or expands when exposed to extreme heat, cutting off the spread of fire in through penetrations. Flame Stopper 5000 seals surfaces with or without movement and will not crack or deteriorate where vibrations occur. Apply Flame Stopper 5000 in interior and exterior applications to stops the spread of toxic fumes, smoke and fire. Flame Stopper 5000 dries to a red flexible seal and can be painted when dry.